Skip to content
Projects
Groups
Snippets
Help
Loading...
Help
Support
Keyboard shortcuts
?
Submit feedback
Contribute to GitLab
Sign in / Register
Toggle navigation
M
MariaDB
Project overview
Project overview
Details
Activity
Releases
Repository
Repository
Files
Commits
Branches
Tags
Contributors
Graph
Compare
Issues
0
Issues
0
List
Boards
Labels
Milestones
Merge Requests
0
Merge Requests
0
CI / CD
CI / CD
Pipelines
Jobs
Schedules
Analytics
Analytics
CI / CD
Repository
Value Stream
Wiki
Wiki
Snippets
Snippets
Members
Members
Collapse sidebar
Close sidebar
Activity
Graph
Create a new issue
Jobs
Commits
Issue Boards
Open sidebar
nexedi
MariaDB
Commits
1731161f
Commit
1731161f
authored
Jul 30, 2001
by
monty@tik.mysql.fi
Browse files
Options
Browse Files
Download
Email Patches
Plain Diff
Fixed optimizer bug in ORDER BY where some ORDER BY parts where ignored.
Extended default arguments to be up to 4095 characters
parent
1ebd29ac
Changes
5
Hide whitespace changes
Inline
Side-by-side
Showing
5 changed files
with
136 additions
and
1042 deletions
+136
-1042
Docs/manual.texi
Docs/manual.texi
+51
-1030
mysql-test/r/order_by.result
mysql-test/r/order_by.result
+31
-0
mysql-test/t/order_by.test
mysql-test/t/order_by.test
+47
-5
mysys/default.c
mysys/default.c
+1
-1
sql/sql_select.cc
sql/sql_select.cc
+6
-6
No files found.
Docs/manual.texi
View file @
1731161f
...
...
@@ -146,1009 +146,6 @@ distribution for that version.
* Function Index:: SQL command, type and function index
* Concept Index:: Concept Index
@detailmenu
--- The Detailed Node Listing ---
General Information About MySQL
* MySQL and MySQL AB::
* MySQL Information Sources::
* Licensing and Support::
* Compatibility::
* Comparisons::
* TODO::
MySQL, MySQL AB, and Open Source
* What-is:: What is @strong{MySQL}?
* What is MySQL AB:: What is @strong{MySQL AB}?
* Manual-info:: About this manual
* Manual conventions:: Conventions used in this manual
* History:: History of @strong{MySQL}
* Features:: The main features of @strong{MySQL}
* Stability:: How stable is @strong{MySQL}?
* Table size::
* Year 2000 compliance:: Year 2000 compliance
MySQL Information Sources
* MySQL-Books::
* General-SQL::
* Useful Links::
* Questions::
MySQL Mailing Lists
* Mailing-list:: The @strong{MySQL} mailing lists
* Asking questions:: Asking questions or reporting bugs
* Bug reports:: How to report bugs or problems
* Answering questions:: Guidelines for answering questions on the mailing list
MySQL Licensing and Support
* Licensing policy:: @strong{MySQL} licensing policy
* Copyright:: Copyrights used by @strong{MySQL}
* Licensing examples:: Example licensing situations
* Cost:: @strong{MySQL} licensing and support costs
* Support:: Types of commercial support
Copyrights Used by MySQL
* Copyright changes:: Possible future copyright changes
Example Licensing Situations
* Products that use MySQL:: Selling products that use @strong{MySQL}
* ISP:: ISP @strong{MySQL} services
* Web server:: Running a web server using @strong{MySQL}.
MySQL Licensing and Support Costs
* Payment information:: Payment information
* Contact information:: Contact information
Types of Commercial Support
* Basic email support:: Basic email support
* Extended email support:: Extended email support
* Login support:: Login support
* Extended login support:: Extended login support
* Telephone support:: Telephone support
* Table handler support:: Support for other table handlers
How Standards-compatible Is MySQL?
* Extensions to ANSI:: @strong{MySQL} extensions to ANSI SQL92
* Differences from ANSI:: @strong{MySQL} differences compared to ANSI SQL92
* ANSI mode:: Running @strong{MySQL} in ANSI mode
* Missing functions:: Functionality missing from @strong{MySQL}
* Standards:: What standards does @strong{MySQL} follow?
* Commit-rollback:: How to cope without @code{COMMIT}-@code{ROLLBACK}
* Bugs::
Functionality Missing from MySQL
* Missing Sub-selects:: Sub-selects
* Missing SELECT INTO TABLE:: @code{SELECT INTO TABLE}
* Missing Transactions:: Transactions
* Missing Triggers:: Triggers
* Missing Foreign Keys:: Foreign Keys
* Broken Foreign KEY::
* Missing Views:: Views
* Missing comments:: @samp{--} as the start of a comment
Foreign Keys
* Broken Foreign KEY:: Reasons NOT to use foreign keys constraints
How MySQL Compares to Other Databases
* Compare mSQL:: How @strong{MySQL} compares to @code{mSQL}
* Protocol differences::
* Compare PostgreSQL:: How @strong{MySQL} compares with PostgreSQL
* MySQL-PostgreSQL features::
How MySQL Compares to @code{mSQL}
* Using mSQL tools:: How to convert @code{mSQL} tools for @strong{MySQL}
How @code{mSQL} and MySQL Client/Server Communications Protocols Differ
* Syntax differences::
How MySQL Compares to PostgreSQL
* MySQL-PostgreSQL goals:: MySQL and PostgreSQL development strategies
Featurevise Comparison of MySQL and PostgreSQL
* MySQL-PostgreSQL benchmarks::
MySQL and the future (The TODO)
* TODO MySQL 4.0:: Things that should be in Version 4.0
* TODO future:: Things that must be done in the near future
* TODO sometime:: Things that have to be done sometime
* TODO unplanned:: Some things we don't have any plans to do
Installing MySQL
* Getting MySQL:: How to get @strong{MySQL}
* Which OS:: Operating systems supported by @strong{MySQL}
* Which version:: Which @strong{MySQL} version to use
* Many versions:: How and when updates are released
* Installation layouts:: Installation layouts
* Installing binary:: Installing a @strong{MySQL} binary distribution
* Installing source:: Installing a @strong{MySQL} source distribution
* Installing source tree:: Installing @strong{MySQL} from development source tree
* Compilation problems:: Problems compiling?
* MIT-pthreads:: MIT-pthreads notes
* Perl support:: Perl installation comments
* Source install system issues:: System-specific issues
* Windows:: Windows notes
* OS/2:: OS/2 notes
* MySQL binaries:: MySQL binaries
* Post-installation:: Post-installation setup and testing
* Installing many servers:: Installing many servers on the same machine
* Upgrade:: Upgrading/Downgrading MySQL
Installing a MySQL Binary Distribution
* Linux-RPM:: Linux RPM files
* Building clients:: Building client programs
* Binary install system issues:: System-specific issues
System-specific Issues
* Binary notes-Linux:: Linux notes for binary distribution
* Binary notes-HP-UX:: HP-UX notes for binary distribution
Installing a MySQL Source Distribution
* Quick install:: Quick installation overview
* Applying patches:: Applying patches
* configure options:: Typical @code{configure} options
Perl Installation Comments
* Perl installation:: Installing Perl on Unix
* ActiveState Perl:: Installing ActiveState Perl on Windows
* Windows Perl:: Installing the @strong{MySQL} Perl distribution on Windows
* Perl support problems:: Problems using the Perl @code{DBI}/@code{DBD} interface
System-specific Issues
* Solaris:: Solaris notes
* Solaris 2.7:: Solaris 2.7 / 2.8 notes
* Solaris x86:: Solaris x86 notes
* SunOS:: SunOS 4 notes
* Linux:: Linux notes (all Linux versions)
* Alpha-DEC-UNIX:: Alpha-DEC-UNIX notes
* Alpha-DEC-OSF1:: Alpha-DEC-OSF1 notes
* SGI-Irix:: SGI-Irix notes
* FreeBSD:: FreeBSD notes
* NetBSD:: NetBSD notes
* OpenBSD:: OpenBSD 2.5 notes
* BSDI:: BSD/OS notes
* SCO:: SCO notes
* SCO Unixware:: SCO Unixware 7.0 notes
* IBM-AIX:: IBM-AIX notes
* HP-UX 10.20:: HP-UX 10.20 notes
* HP-UX 11.x:: HP-UX 11.x notes
* Mac OS X:: Mac OS X notes
* BEOS:: BeOS Notes
Linux Notes (All Linux Versions)
* Linux-x86:: Linux-x86 notes
* Linux-RedHat50:: RedHat 5.0 notes
* Linux-RedHat51:: RedHat 5.1 notes
* Linux-SPARC:: Linux-SPARC notes
* Linux-Alpha:: Linux-Alpha notes
* MKLinux:: MkLinux notes
* Qube2:: Qube2 Linux notes
* Linux-Ia64:: Linux-Ia64 notes
OpenBSD Notes
* OpenBSD 2.5:: OpenBSD 2.5 Notes
* OpenBSD 2.8:: OpenBSD 2.8 Notes
BSD/OS Notes
* BSDI2:: BSD/OS 2.x notes
* BSDI3:: BSD/OS 3.x notes
* BSDI4:: BSD/OS 4.x notes
Mac OS X Notes
* Mac OS X Public Data::
* Mac OS X Server::
Windows Notes
* Windows installation:: Installing @strong{MySQL} on Windows
* Win95 start:: Starting @strong{MySQL} on Win95 / Win98
* NT start:: Starting @strong{MySQL} on NT / Win2000
* Windows running:: Running @strong{MySQL} on Windows
* Windows and SSH:: Connecting to a remote @strong{MySQL} from Windows with SSH
* Windows symbolic links:: Splitting data across different disks under Win32
* Windows compiling:: Compiling MySQL clients on Windows.
* Windows vs Unix:: @strong{MySQL}-Windows compared to Unix @strong{MySQL}
Post-installation Setup and Testing
* mysql_install_db:: Problems running @code{mysql_install_db}
* Starting server:: Problems starting the @strong{MySQL} server
* Automatic start:: Starting and stopping @strong{MySQL} automatically
* Command-line options:: Command-line options
* Option files:: Option files
Upgrading/Downgrading MySQL
* Upgrading-from-3.22:: Upgrading from a 3.22 version to 3.23
* Upgrading-from-3.21:: Upgrading from a 3.21 version to 3.22
* Upgrading-from-3.20:: Upgrading from a 3.20 version to 3.21
* Upgrading-to-arch:: Upgrading to another architecture
The MySQL Access Privilege System
* General security:: General security
* Security:: How to make @strong{MySQL} secure against crackers
* Privileges options::
* What Privileges:: What the privilege system does
* User names:: @strong{MySQL} user names and passwords
* Connecting:: Connecting to the @strong{MySQL} server
* Password security:: Keeping your password secure
* Privileges provided:: Privileges provided by @strong{MySQL}
* Privileges:: How the privilege system works
* Connection access:: Access control, stage 1: Connection verification
* Request access:: Access control, stage 2: Request verification
* Privilege changes:: When privilege changes take effect
* Default privileges:: Setting up the initial @strong{MySQL} privileges
* Adding users:: Adding new users to @strong{MySQL}
* Passwords:: How to set up passwords
* Access denied:: Causes of @code{Access denied} errors
MySQL Language Reference
* Literals:: Literals: How to write strings and numbers
* Variables:: User variables
* Column types:: Column types
* Functions:: Functions
* CREATE DATABASE:: @code{CREATE DATABASE} syntax
* DROP DATABASE:: @code{DROP DATABASE} syntax
* CREATE TABLE:: @code{CREATE TABLE} syntax
* ALTER TABLE:: @code{ALTER TABLE} syntax
* RENAME TABLE:: @code{RENAME TABLE} syntax
* DROP TABLE:: @code{DROP TABLE} syntax
* OPTIMIZE TABLE:: @code{OPTIMIZE TABLE} syntax
* CHECK TABLE:: @code{CHECK TABLE} syntax
* BACKUP TABLE:: @code{BACKUP TABLE} syntax
* RESTORE TABLE:: @code{RESTORE TABLE} syntax
* ANALYZE TABLE:: @code{ANALYZE TABLE} syntax
* REPAIR TABLE:: @code{REPAIR TABLE} syntax
* DELETE:: @code{DELETE} syntax
* TRUNCATE:: @code{TRUNCATE} syntax
* SELECT:: @code{SELECT} syntax
* JOIN:: @code{JOIN} syntax
* INSERT:: @code{INSERT} syntax
* REPLACE:: @code{REPLACE} syntax
* LOAD DATA:: @code{LOAD DATA INFILE} syntax
* UPDATE:: @code{UPDATE} syntax
* USE:: @code{USE} syntax
* FLUSH:: @code{FLUSH} syntax (clearing caches)
* KILL:: @code{KILL} syntax
* SHOW:: @code{SHOW} syntax (Get information about tables, columns, ...)
* EXPLAIN:: @code{EXPLAIN} syntax (Get information about a @code{SELECT})
* DESCRIBE:: @code{DESCRIBE} syntax (Get information about names of columns)
* COMMIT:: @code{BEGIN/COMMIT/ROLLBACK} syntax
* LOCK TABLES:: @code{LOCK TABLES/UNLOCK TABLES} syntax
* SET OPTION:: @code{SET OPTION} syntax
* SET TRANSACTION:: @code{SET TRANSACTION} syntax
* GRANT:: @code{GRANT} and @code{REVOKE} syntax
* CREATE INDEX:: @code{CREATE INDEX} syntax
* DROP INDEX:: @code{DROP INDEX} syntax
* Comments:: Comment syntax
* CREATE FUNCTION:: @code{CREATE FUNCTION} syntax
* Reserved words:: Is @strong{MySQL} picky about reserved words?
Literals: How to Write Strings and Numbers
* String syntax:: Strings
* Number syntax:: Numbers
* Hexadecimal values:: Hexadecimal values
* NULL values:: @code{NULL} values
* Legal names:: Database, Table, Index, Column, and Alias Names
Database, Table, Index, Column, and Alias Names
* Name case sensitivity:: Case sensitivity in names
Column Types
* Storage requirements:: Column type storage requirements
* Numeric types:: Numeric types
* Date and time types:: Date and time types
* String types:: String types
* Choosing types:: Choosing the right type for a column
* Indexes:: Column indexes
* Multiple-column indexes:: Multiple-column indexes
* Other-vendor column types:: Using column types from other database engines
Date and Time Types
* Y2K issues:: Y2K issues and date types
* DATETIME:: The @code{DATETIME}, @code{DATE} and @code{TIMESTAMP} types
* TIME:: The @code{TIME} type
* YEAR:: The @code{YEAR} type
String Types
* CHAR:: The @code{CHAR} and @code{VARCHAR} types
* BLOB:: The @code{BLOB} and @code{TEXT} types
* ENUM:: The @code{ENUM} type
* SET:: The @code{SET} type
Functions for Use in @code{SELECT} and @code{WHERE} Clauses
* Grouping functions:: Grouping functions
* Arithmetic functions:: Normal arithmetic operations
* Bit functions:: Bit functions
* Logical functions:: Logical operations
* Comparison functions:: Comparison operators
* String comparison functions:: String comparison functions
* Casts:: Cast operators
* Control flow functions:: Control flow functions
* Mathematical functions:: Mathematical functions
* String functions:: String functions
* Date and time functions:: Date and time functions
* Miscellaneous functions:: Miscellaneous functions
* Group by functions:: Functions for @code{GROUP BY} clause
@code{CREATE TABLE} Syntax
* Silent column changes:: Silent column changes
@code{INSERT} Syntax
* INSERT SELECT::
* INSERT DELAYED::
@code{SHOW} Syntax
* SHOW DATABASE INFO::
* SHOW TABLE STATUS::
* SHOW STATUS::
* SHOW VARIABLES::
* SHOW LOGS::
* SHOW PROCESSLIST::
* SHOW GRANTS::
* SHOW CREATE TABLE::
MySQL Table Types
* MyISAM:: MyISAM tables
* MERGE:: MERGE tables
* ISAM:: ISAM tables
* HEAP:: HEAP tables
* InnoDB:: InnoDB tables
* BDB:: BDB or Berkeley_db tables
MyISAM Tables
* Key space:: Space needed for keys
* MyISAM table formats:: MyISAM table formats
* MyISAM table problems::
MyISAM Table Formats
* Static format:: Static (Fixed-length) table characteristics
* Dynamic format:: Dynamic table characteristics
* Compressed format:: Compressed table characteristics
MyISAM table problems.
* Corrupted MyISAM tables::
* MyISAM table close::
InnoDB Tables
* InnoDB overview:: InnoDB tables overview
* InnoDB start:: InnoDB startup options
* InnoDB init:: Creating InnoDB table space.
* Using InnoDB tables:: Creating InnoDB tables
* Adding and removing:: Adding and removing InnoDB data and log files
* Backing up:: Backing up and recovering an InnoDB database
* Moving:: Moving an InnoDB database to another machine
* InnoDB transaction model:: InnoDB transaction model.
* Implementation:: Implementation of multiversioning
* Table and index:: Table and index structures
* File space management:: File space management and disk i/o
* Error handling:: Error handling
* InnoDB restrictions:: Some restrictions on InnoDB tables
* InnoDB contact information:: InnoDB contact information.
Creating InnoDB table space
* Error creating InnoDB::
Backing up and recovering an InnoDB database
* InnoDB checkpoints::
InnoDB transaction model
* InnoDB consistent read::
* InnoDB locking reads::
* InnoDB Next-key locking::
* InnoDB Locks set::
* InnoDB Deadlock detection::
Table and index structures
* InnoDB physical structure::
* InnoDB Insert buffering::
* InnoDB Adaptive hash::
* InnoDB Physical record::
File space management and disk i/o
* InnoDB Disk i/o::
* InnoDB File space::
* InnoDB File Defragmenting::
BDB or Berkeley_DB Tables
* BDB overview:: Overview of BDB Tables
* BDB install:: Installing BDB
* BDB start:: BDB startup options
* BDB characteristic:: Some characteristic of @code{BDB} tables:
* BDB TODO:: Some things we need to fix for BDB in the near future:
* BDB portability:: Operating systems supported by @strong{BDB}
* BDB errors:: Errors You May Get When Using BDB Tables
MySQL Tutorial
* Connecting-disconnecting:: Connecting to and disconnecting from the server
* Entering queries:: Entering queries
* Database use:: Creating and using a database
* Getting information:: Getting information about databases and tables
* Examples:: Examples
* Batch mode:: Using @code{mysql} in batch mode
* Twin:: Queries from twin project
Creating and Using a Database
* Creating database:: Creating a database
* Creating tables:: Creating a table
* Loading tables:: Loading data into a table
* Retrieving data:: Retrieving information from a table
Retrieving Information from a Table
* Selecting all:: Selecting all data
* Selecting rows:: Selecting particular rows
* Selecting columns:: Selecting particular columns
* Sorting rows:: Sorting rows
* Date calculations:: Date calculations
* Working with NULL:: Working with @code{NULL} values
* Pattern matching:: Pattern matching
* Counting rows:: Counting rows
* Multiple tables::
Examples of Common Queries
* example-Maximum-column:: The maximum value for a column
* example-Maximum-row:: The row holding the maximum of a certain column
* example-Maximum-column-group:: Maximum of column per group
* example-Maximum-column-group-row:: The rows holding the group-wise maximum of a certain field
* example-user-variables:: Using user variables
* example-Foreign keys:: Using foreign keys
* Searching on two keys::
* Calculating days::
Queries from Twin Project
* Twin pool:: Find all non-distributed twins
* Twin event:: Show a table on twin pair status
MySQL Server Functions
* Languages:: What languages are supported by @strong{MySQL}?
What Languages Are Supported by MySQL?
* Character sets:: The character set used for data and sorting
* Adding character set:: Adding a new character set
* Character arrays:: The character definition arrays
* String collating:: String collating support
* Multi-byte characters:: Multi-byte character support
Replication in MySQL
* Replication Intro:: Introduction
* Replication Implementation:: Replication Implementation Overview
* Replication HOWTO:: HOWTO
* Replication Features:: Replication Features
* Replication Options:: Replication Options in my.cnf
* Replication SQL:: SQL Commands related to replication
* Replication FAQ:: Frequently Asked Questions about replication
* Replication Problems:: Troubleshooting Replication.
MySQL Full-text Search
* Fulltext Fine-tuning::
* Fulltext Features to Appear in MySQL 4.0::
* Fulltext TODO::
Getting Maximum Performance from MySQL
* Optimize Basics:: Optimization overview
* System:: System/Compile time and startup parameter tuning
* Data size:: Get your data as small as possible
* MySQL indexes:: How @strong{MySQL} uses indexes
* Query Speed:: Speed of queries that access or update data
* Tips:: Other optimization tips
* Benchmarks:: Using your own benchmarks
* Design:: Design choices
* Design Limitations:: MySQL design limitations/tradeoffs
* Portability:: Portability
* Internal use:: What have we used MySQL for?
System/Compile Time and Startup Parameter Tuning
* Compile and link options:: How compiling and linking affects the speed of MySQL
* Disk issues:: Disk issues
* Symbolic links:: Using Symbolic Links
* Server parameters:: Tuning server parameters
* Table cache:: How MySQL opens and closes tables
* Creating many tables:: Drawbacks of creating large numbers of tables in the same database
* Open tables:: Why so many open tables?
* Memory use:: How MySQL uses memory
* Internal locking:: How MySQL locks tables
* Table locking:: Table locking issues
* DNS::
Using Symbolic Links
* Symbolic links to database::
* Symbolic links to tables::
Speed of Queries that Access or Update Data
* Estimating performance:: Estimating query performance
* SELECT speed:: Speed of @code{SELECT} queries
* Where optimizations:: How MySQL optimizes @code{WHERE} clauses
* DISTINCT optimization:: How MySQL Optimizes @code{DISTINCT}
* LEFT JOIN optimization:: How MySQL optimizes @code{LEFT JOIN}
* LIMIT optimization:: How MySQL optimizes @code{LIMIT}
* Insert speed:: Speed of @code{INSERT} queries
* Update speed:: Speed of @code{UPDATE} queries
* Delete speed:: Speed of @code{DELETE} queries
MySQL Utilites
* Programs:: What do the executables do?
* mysqld-max:: mysqld-max, An extended mysqld server
* safe_mysqld:: safe_mysqld, the wrapper around mysqld
* mysqld_multi:: Program for managing multiple @strong{MySQL} servers
* mysql:: The command line tool
* mysqladmin:: Administering a @strong{MySQL} server
* mysqldump:: Dumping the structure and data from @strong{MySQL} databases and tables
* mysqlhotcopy:: Copying @strong{MySQL} Databases and Tables
* mysqlimport:: Importing data from text files
* perror:: Displaying error messages
* mysqlshow:: Showing databases, tables and columns
* myisampack:: The @strong{MySQL} compressed read-only table generator
Maintaining a MySQL Installation
* Table maintenance:: Table maintenance and crash recovery
* Using mysqlcheck:: Using mysqlcheck for maintenance and recovery
* Maintenance regimen:: Setting up a table maintenance regimen
* Table-info:: Getting information about a table
* Crash recovery:: Using @code{myisamchk} for crash recovery
* Log file maintenance:: Log file maintenance
Using @code{myisamchk} for Table Maintenance and Crash Recovery
* myisamchk syntax:: @code{myisamchk} invocation syntax
* myisamchk memory:: @code{myisamchk} memory usage
@code{myisamchk} Invocation Syntax
* myisamchk general options::
* myisamchk check options::
* myisamchk repair options::
* myisamchk other options::
Using @code{myisamchk} for Crash Recovery
* Check:: How to check tables for errors
* Repair:: How to repair tables
* Optimization:: Table optimization
Adding New Functions to MySQL
* Adding UDF:: Adding a new user-definable function
* Adding native function:: Adding a new native function
Adding a New User-definable Function
* UDF calling sequences:: UDF calling sequences
* UDF arguments:: Argument processing
* UDF return values:: Return values and error handling
* UDF compiling:: Compiling and installing user-definable functions
Adding New Procedures to MySQL
* procedure analyse:: Procedure analyse
* Writing a procedure:: Writing a procedure.
MySQL ODBC Support
* Installing MyODBC:: How to install MyODBC
* ODBC administrator:: How to fill in the various fields in the ODBC administrator program
* MyODBC connect parameters::
* ODBC Problems:: How to report problems with @strong{MySQL} ODBC
* MyODBC clients:: Programs known to work with @strong{MyODBC}
* ODBC and last_insert_id:: How to get the value of an @code{AUTO_INCREMENT} column in ODBC
* MyODBC bug report:: Reporting problems with MyODBC
Using MySQL with Some Common Programs
* Apache:: Using @strong{MySQL} with Apache
* Borland C++::
Problems and Common Errors
* What is crashing:: How to determine what is causing problems
* Crashing:: What to do if @strong{MySQL} keeps crashing
* Link errors:: Problems when linking with the @strong{MySQL} client library
* Common errors:: Some common errors when using @strong{MySQL}
* Full disk:: How @strong{MySQL} handles a full disk
* Multiple sql commands:: How to run SQL commands from a text file
* Temporary files:: Where @strong{MySQL} stores temporary files
* Problems with mysql.sock:: How to protect @file{/tmp/mysql.sock}
* Changing MySQL user:: How to run @strong{MySQL} as a normal user
* Resetting permissions:: How to reset a forgotten password.
* File permissions :: Problems with file permissions
* Not enough file handles:: File not found
* Using DATE:: Problems using @code{DATE} columns
* Timezone problems:: Timezone problems
* Case sensitivity:: Case sensitivity in searches
* Problems with NULL:: Problems with @code{NULL} values
* Problems with alias:: Problems with @code{alias}
* Deleting from related tables:: Deleting rows from related tables
* No matching rows:: Solving problems with no matching rows
* ALTER TABLE problems:: Problems with @code{ALTER TABLE}.
* Change column order:: How to change the order of columns in a table
* Temporary table problems::
Some Common Errors When Using MySQL
* Error Access denied:: @code{Access denied} Error
* Gone away:: @code{MySQL server has gone away} error
* Can not connect to server:: @code{Can't connect to [local] MySQL server} error
* Blocked host:: @code{Host '...' is blocked} error
* Too many connections:: @code{Too many connections} error
* Non-transactional tables:: @code{Some non-transactional changed tables couldn't be rolled back} Error
* Out of memory:: @code{Out of memory} error
* Packet too large:: @code{Packet too large} error
* Communication errors:: Communication errors / Aborted connection
* Full table:: @code{The table is full} error
* Cannot create:: @code{Can't create/write to file} Error
* Commands out of sync:: @code{Commands out of sync} error in client
* Ignoring user:: @code{Ignoring user} error
* Cannot find table:: @code{Table 'xxx' doesn't exist} error
* Cannot initialize character set::
Solving Some Common Problems with MySQL
* Log Replication:: Database replication with update log
* Backup:: Database backups
* Multiple servers:: Running multiple @strong{MySQL} servers on the same machine
The MySQL log files
* Error log::
* Query log::
* Update log::
* Binary log::
* Slow query log::
MySQL APIs
* C:: @strong{MySQL} C API
* Perl:: @strong{MySQL} Perl API
* Eiffel:: @strong{MySQL} Eiffel wrapper
* Java:: @strong{MySQL} Java connectivity (JDBC)
* PHP:: @strong{MySQL} PHP API
* Cplusplus:: @strong{MySQL} C++ APIs
* Python:: @strong{MySQL} Python APIs
* Tcl:: @strong{MySQL} Tcl APIs
MySQL C API
* C API datatypes:: C API Datatypes
* C API function overview:: C API Function Overview
* C API functions:: C API Function Descriptions
* C API problems::
* Thread-safe clients::
C API Function Descriptions
* mysql_affected_rows:: @code{mysql_affected_rows()}
* mysql_close:: @code{mysql_close()}
* mysql_connect:: @code{mysql_connect()}
* mysql_change_user:: @code{mysql_change_user()}
* mysql_character_set_name:: @code{mysql_character_set_name()}
* mysql_create_db:: @code{mysql_create_db()}
* mysql_data_seek:: @code{mysql_data_seek()}
* mysql_debug:: @code{mysql_debug()}
* mysql_drop_db:: @code{mysql_drop_db()}
* mysql_dump_debug_info:: @code{mysql_dump_debug_info()}
* mysql_eof:: @code{mysql_eof()}
* mysql_errno:: @code{mysql_errno()}
* mysql_error:: @code{mysql_error()}
* mysql_escape_string:: @code{mysql_escape_string()}
* mysql_fetch_field:: @code{mysql_fetch_field()}
* mysql_fetch_fields:: @code{mysql_fetch_fields()}
* mysql_fetch_field_direct:: @code{mysql_fetch_field_direct()}
* mysql_fetch_lengths:: @code{mysql_fetch_lengths()}
* mysql_fetch_row:: @code{mysql_fetch_row()}
* mysql_field_count:: @code{mysql_field_count()}
* mysql_field_seek:: @code{mysql_field_seek()}
* mysql_field_tell:: @code{mysql_field_tell()}
* mysql_free_result:: @code{mysql_free_result()}
* mysql_get_client_info:: @code{mysql_get_client_info()}
* mysql_get_host_info:: @code{mysql_get_host_info()}
* mysql_get_proto_info:: @code{mysql_get_proto_info()}
* mysql_get_server_info:: @code{mysql_get_server_info()}
* mysql_info:: @code{mysql_info()}
* mysql_init:: @code{mysql_init()}
* mysql_insert_id:: @code{mysql_insert_id()}
* mysql_kill:: @code{mysql_kill()}
* mysql_list_dbs:: @code{mysql_list_dbs()}
* mysql_list_fields:: @code{mysql_list_fields()}
* mysql_list_processes:: @code{mysql_list_processes()}
* mysql_list_tables:: @code{mysql_list_tables()}
* mysql_num_fields:: @code{mysql_num_fields()}
* mysql_num_rows:: @code{mysql_num_rows()}
* mysql_options:: @code{mysql_options()}
* mysql_ping:: @code{mysql_ping()}
* mysql_query:: @code{mysql_query()}
* mysql_real_connect:: @code{mysql_real_connect()}
* mysql_real_escape_string:: @code{mysql_real_escape_string()}
* mysql_real_query:: @code{mysql_real_query()}
* mysql_reload:: @code{mysql_reload()}
* mysql_row_seek:: @code{mysql_row_seek()}
* mysql_row_tell:: @code{mysql_row_tell()}
* mysql_select_db:: @code{mysql_select_db()}
* mysql_shutdown:: @code{mysql_shutdown()}
* mysql_stat:: @code{mysql_stat()}
* mysql_store_result:: @code{mysql_store_result()}
* mysql_thread_id:: @code{mysql_thread_id()}
* mysql_use_result:: @code{mysql_use_result()}
Common questions and problems when using the C API
* NULL mysql_store_result::
* Query results::
* Getting unique ID::
* C API linking problems::
Why Is It that After @code{mysql_query()} Returns Success, @code{mysql_store_result()} Sometimes Returns @code{NULL?}
* Query results::
* Getting unique ID::
* C API linking problems::
MySQL Perl API
* DBI with DBD:: @code{DBI} with @code{DBD::mysql}
* Perl DBI Class:: The @code{DBI} interface
* DBI-info:: More @code{DBI}/@code{DBD} information
MySQL PHP API
* PHP problems:: Common problems with MySQL and PHP
MySQL Internals
* MySQL threads:: MySQL threads
* MySQL test suite:: MySQL test suite
MySQL Test Suite
* running mysqltest::
* extending mysqltest::
* Reporting mysqltest bugs::
Credits
* Developers::
* Contributors::
* Supporters::
MySQL change history
* News-4.0.x:: Changes in release 4.0.x (Development; Alpha)
* News-3.23.x:: Changes in release 3.23.x (Stable)
* News-3.22.x:: Changes in release 3.22.x (Older; Still supported)
* News-3.21.x:: Changes in release 3.21.x
* News-3.20.x:: Changes in release 3.20.x
* News-3.19.x:: Changes in release 3.19.x
Changes in release 4.0.x (Development; Alpha)
* News-4.0.0:: Changes in release 4.0.0
Changes in release 3.23.x (Stable)
* News-3.23.40:: Changes in release 3.23.40
* News-3.23.39:: Changes in release 3.23.39
* News-3.23.38:: Changes in release 3.23.38
* News-3.23.37:: Changes in release 3.23.37
* News-3.23.36:: Changes in release 3.23.36
* News-3.23.35:: Changes in release 3.23.35
* News-3.23.34a:: Changes in release 3.23.34a
* News-3.23.34:: Changes in release 3.23.34
* News-3.23.33:: Changes in release 3.23.33
* News-3.23.32:: Changes in release 3.23.32
* News-3.23.31:: Changes in release 3.23.31
* News-3.23.30:: Changes in release 3.23.30
* News-3.23.29:: Changes in release 3.23.29
* News-3.23.28:: Changes in release 3.23.28
* News-3.23.27:: Changes in release 3.23.27
* News-3.23.26:: Changes in release 3.23.26
* News-3.23.25:: Changes in release 3.23.25
* News-3.23.24:: Changes in release 3.23.24
* News-3.23.23:: Changes in release 3.23.23
* News-3.23.22:: Changes in release 3.23.22
* News-3.23.21:: Changes in release 3.23.21
* News-3.23.20:: Changes in release 3.23.20
* News-3.23.19:: Changes in release 3.23.19
* News-3.23.18:: Changes in release 3.23.18
* News-3.23.17:: Changes in release 3.23.17
* News-3.23.16:: Changes in release 3.23.16
* News-3.23.15:: Changes in release 3.23.15
* News-3.23.14:: Changes in release 3.23.14
* News-3.23.13:: Changes in release 3.23.13
* News-3.23.12:: Changes in release 3.23.12
* News-3.23.11:: Changes in release 3.23.11
* News-3.23.10:: Changes in release 3.23.10
* News-3.23.9:: Changes in release 3.23.9
* News-3.23.8:: Changes in release 3.23.8
* News-3.23.7:: Changes in release 3.23.7
* News-3.23.6:: Changes in release 3.23.6
* News-3.23.5:: Changes in release 3.23.5
* News-3.23.4:: Changes in release 3.23.4
* News-3.23.3:: Changes in release 3.23.3
* News-3.23.2:: Changes in release 3.23.2
* News-3.23.1:: Changes in release 3.23.1
* News-3.23.0:: Changes in release 3.23.0
Changes in release 3.22.x (Older; Still supported)
* News-3.22.35:: Changes in release 3.22.35
* News-3.22.34:: Changes in release 3.22.34
* News-3.22.33:: Changes in release 3.22.33
* News-3.22.32:: Changes in release 3.22.32
* News-3.22.31:: Changes in release 3.22.31
* News-3.22.30:: Changes in release 3.22.30
* News-3.22.29:: Changes in release 3.22.29
* News-3.22.28:: Changes in release 3.22.28
* News-3.22.27:: Changes in release 3.22.27
* News-3.22.26:: Changes in release 3.22.26
* News-3.22.25:: Changes in release 3.22.25
* News-3.22.24:: Changes in release 3.22.24
* News-3.22.23:: Changes in release 3.22.23
* News-3.22.22:: Changes in release 3.22.22
* News-3.22.21:: Changes in release 3.22.21
* News-3.22.20:: Changes in release 3.22.20
* News-3.22.19:: Changes in release 3.22.19
* News-3.22.18:: Changes in release 3.22.18
* News-3.22.17:: Changes in release 3.22.17
* News-3.22.16:: Changes in release 3.22.16
* News-3.22.15:: Changes in release 3.22.15
* News-3.22.14:: Changes in release 3.22.14
* News-3.22.13:: Changes in release 3.22.13
* News-3.22.12:: Changes in release 3.22.12
* News-3.22.11:: Changes in release 3.22.11
* News-3.22.10:: Changes in release 3.22.10
* News-3.22.9:: Changes in release 3.22.9
* News-3.22.8:: Changes in release 3.22.8
* News-3.22.7:: Changes in release 3.22.7
* News-3.22.6:: Changes in release 3.22.6
* News-3.22.5:: Changes in release 3.22.5
* News-3.22.4:: Changes in release 3.22.4
* News-3.22.3:: Changes in release 3.22.3
* News-3.22.2:: Changes in release 3.22.2
* News-3.22.1:: Changes in release 3.22.1
* News-3.22.0:: Changes in release 3.22.0
Changes in release 3.21.x
* News-3.21.33:: Changes in release 3.21.33
* News-3.21.32:: Changes in release 3.21.32
* News-3.21.31:: Changes in release 3.21.31
* News-3.21.30:: Changes in release 3.21.30
* News-3.21.29:: Changes in release 3.21.29
* News-3.21.28:: Changes in release 3.21.28
* News-3.21.27:: Changes in release 3.21.27
* News-3.21.26:: Changes in release 3.21.26
* News-3.21.25:: Changes in release 3.21.25
* News-3.21.24:: Changes in release 3.21.24
* News-3.21.23:: Changes in release 3.21.23
* News-3.21.22:: Changes in release 3.21.22
* News-3.21.21a:: Changes in release 3.21.21a
* News-3.21.21:: Changes in release 3.21.21
* News-3.21.20:: Changes in release 3.21.20
* News-3.21.19:: Changes in release 3.21.19
* News-3.21.18:: Changes in release 3.21.18
* News-3.21.17:: Changes in release 3.21.17
* News-3.21.16:: Changes in release 3.21.16
* News-3.21.15:: Changes in release 3.21.15
* News-3.21.14b:: Changes in release 3.21.14b
* News-3.21.14a:: Changes in release 3.21.14a
* News-3.21.13:: Changes in release 3.21.13
* News-3.21.12:: Changes in release 3.21.12
* News-3.21.11:: Changes in release 3.21.11
* News-3.21.10:: Changes in release 3.21.10
* News-3.21.9:: Changes in release 3.21.9
* News-3.21.8:: Changes in release 3.21.8
* News-3.21.7:: Changes in release 3.21.7
* News-3.21.6:: Changes in release 3.21.6
* News-3.21.5:: Changes in release 3.21.5
* News-3.21.4:: Changes in release 3.21.4
* News-3.21.3:: Changes in release 3.21.3
* News-3.21.2:: Changes in release 3.21.2
* News-3.21.0:: Changes in release 3.21.0
Changes in release 3.20.x
* News-3.20.18:: Changes in release 3.20.18
* News-3.20.17:: Changes in release 3.20.17
* News-3.20.16:: Changes in release 3.20.16
* News-3.20.15:: Changes in release 3.20.15
* News-3.20.14:: Changes in release 3.20.14
* News-3.20.13:: Changes in release 3.20.13
* News-3.20.11:: Changes in release 3.20.11
* News-3.20.10:: Changes in release 3.20.10
* News-3.20.9:: Changes in release 3.20.9
* News-3.20.8:: Changes in release 3.20.8
* News-3.20.7:: Changes in release 3.20.7
* News-3.20.6:: Changes in release 3.20.6
* News-3.20.3:: Changes in release 3.20.3
* News-3.20.0:: Changes in releases 3.20.0
Changes in release 3.19.x
* News-3.19.5:: Changes in release 3.19.5
* News-3.19.4:: Changes in release 3.19.4
* News-3.19.3:: Changes in release 3.19.3
Comments on porting to other systems
* Debugging server:: Debugging a @strong{MySQL} server
* Debugging client:: Debugging a @strong{MySQL} client
* The DBUG package:: The DBUG package
* Locking methods:: Locking methods
* RTS-threads:: Comments about RTS threads
* Thread packages:: Differences between different thread packages
Debugging a MySQL server
* Compiling for debugging::
* Making trace files::
* Using gdb on mysqld::
* Using stack trace::
* Using log files::
* Reproduceable test case::
@end detailmenu
@end menu
@cindex overview
...
...
@@ -10310,10 +9307,10 @@ You should also add /etc/my.cnf:
@example
[safe_mysqld]
open
_files_
limit=8192
open
-files-
limit=8192
@end example
The above should allow @strong{MySQL} to create up to 8192 connections
/
files.
The above should allow @strong{MySQL} to create up to 8192 connections
+
files.
The @code{STACK_SIZE} constant in LinuxThreads controls the spacing of thread
stacks in the address space. It needs to be large enough so that there will
...
...
@@ -24806,17 +23803,9 @@ are locked by the current thread are automatically unlocked when the
thread issues another @code{LOCK TABLES}, or when the connection to the
server is closed.
The main reasons to use @code{LOCK TABLES} are:
@itemize @bullet
@item
Emulate transactions with not transaction safe tables.
@item
To get more speed with @code{MyISAM} tables when inserting/updating data
over many statements. The main reason this gives more speed is that
@strong{MySQL} will not flush the key cache for the locked tables until
@code{UNLOCK TABLES} is called.
@end itemize
The main reasons to use @code{LOCK TABLES} are for emulating transactions
or getting more speed when updating tables. This is explained in more
detail later.
If a thread obtains a @code{READ} lock on a table, that thread (and all other
threads) can only read from the table. If a thread obtains a @code{WRITE}
...
...
@@ -24829,8 +23818,10 @@ execute while the lock is held. This can't however be used if you are
going to manipulate the database files outside @strong{MySQL} while you
hold the lock.
Each thread waits (without timing out) until it obtains all the locks it has
requested.
When you use @code{LOCK TABLES}, you must lock all tables that you are
going to use and you must use the same alias that you are going to use
in your queries! If you are using a table multiple times in a query
(with aliases), you must get a lock for each alias!
@code{WRITE} locks normally have higher priority than @code{READ} locks, to
ensure that updates are processed as soon as possible. This means that if one
...
...
@@ -24842,15 +23833,32 @@ locks while the thread is waiting for the @code{WRITE} lock. You should only
use @code{LOW_PRIORITY WRITE} locks if you are sure that there will
eventually be a time when no threads will have a @code{READ} lock.
@code{LOCK TABLES} and @code{UNLOCK TABLES} both commits any active
transactions.
@code{LOCK TABLES} works as follows:
@enumerate
@item
Sort all tables to be locked in a internally defined order (from the
user standpoint the order is undefined).
@item
If a table is locked with a read and a write lock, put the write lock
before the read lock.
@item
Lock one table at a time until the thread gets all locks.
@end enumerate
This policy ensures that table locking is deadlock free. There is
however other things one needs to be aware of with this schema:
When you use @code{LOCK TABLES}, you must lock all tables that you are
going to use and you must use the same alias that you are going to use
in your queries! If you are using a table multiple times in a query
(with aliases), you must get a lock for each alias! This policy ensures
that table locking is deadlock free and makes the locking code smaller,
simpler and much faster.
If you are using a @code{LOW_PRIORITY_WRITE} lock for a table, this
means only that @strong{MySQL} will wait for this particlar lock until
there is no threads that wants a @code{READ} lock. When the thread has
got the @code{WRITE} lock and is waiting to get the lock for the next
table in the lock table list, all other threads will wait for the
@code{WRITE} lock to be released. If this becomes a serious problem
with your application, you should consider converting some of your
tables to transactions safe tables.
You can safely kill a thread that is waiting for a table lock with
@code{KILL}. @xref{KILL}.
Note that you should @strong{NOT} lock any tables that you are using with
@code{INSERT DELAYED}. This is because that in this case the @code{INSERT}
...
...
@@ -24867,6 +23875,12 @@ If you are going to run many operations on a bunch of tables, it's much
faster to lock the tables you are going to use. The downside is, of course,
that no other thread can update a @code{READ}-locked table and no other
thread can read a @code{WRITE}-locked table.
The reason some things are faster under @code{LOCK TABLES} is that
@strong{MySQL} will not flush the key cache for the locked tables until
@code{UNLOCK TABLES} is called (normally the key cache is flushed after
each SQL statement). This speeds up inserting/updateing/deletes on
@code{MyISAM} tables.
@item
If you are using a table handler in @strong{MySQL} that doesn't support
transactions, you must use @code{LOCK TABLES} if you want to ensure that
...
...
@@ -24898,7 +23912,7 @@ table in the server and implemented with @code{pthread_mutex_lock()} and
See @ref{Internal locking}, for more information on locking policy.
You can
also
lock all tables in all databases with read locks with the
You can lock all tables in all databases with read locks with the
@code{FLUSH TABLES WITH READ LOCK} command. @xref{FLUSH}. This is very
convenient way to get backups if you have a file system, like Veritas,
that can take snapshots in time.
...
...
@@ -46299,8 +45313,6 @@ For making @code{mysqlaccess} more secure.
@item Albert Chin-A-Young.
Configure updates for Tru64, large file support and better TCP wrappers
support.
@item Valueclick Inc.
For sponsoring the optimize section in this manual.
@end table
Other contributors, bugfinders, and testers: James H. Thompson, Maurizio
...
...
@@ -46496,6 +45508,7 @@ users use this code as the rest of the code and because of this we are
not yet 100% confident in this code.
@menu
* News-3.23.41::
* News-3.23.40:: Changes in release 3.23.40
* News-3.23.39:: Changes in release 3.23.39
* News-3.23.38:: Changes in release 3.23.38
...
...
@@ -46540,7 +45553,15 @@ not yet 100% confident in this code.
* News-3.23.0:: Changes in release 3.23.0
@end menu
@node News-3.23.40, News-3.23.39, News-3.23.x, News-3.23.x
@node News-3.23.41, News-3.23.40, News-3.23.x, News-3.23.x
@appendixsubsec Changes in release 3.23.41
@itemize @bullet
@item
Fixed optimizing bug in @code{ORDER BY} where some @code{ORDER BY} parts
where wrongly removed.
@end itemize
@node News-3.23.40, News-3.23.39, News-3.23.41, News-3.23.x
@appendixsubsec Changes in release 3.23.40
@itemize @bullet
@item
mysql-test/r/order_by.result
View file @
1731161f
...
...
@@ -111,3 +111,34 @@ DateOfAction TransactionID
member_id nickname voornaam
1
2
gid sid uid
104620 5 15
103867 5 27
103962 5 27
104619 5 75
104505 5 117
103853 5 250
gid sid uid
104620 5 15
103867 5 27
103962 5 27
104619 5 75
104505 5 117
103853 5 250
table type possible_keys key key_len ref rows Extra
t1 index PRIMARY PRIMARY 4 NULL 6 Using index
t2 eq_ref PRIMARY,uid PRIMARY 4 t1.gid 1
t3 eq_ref PRIMARY PRIMARY 2 t2.uid 1 where used; Using index
table type possible_keys key key_len ref rows Extra
t1 index PRIMARY PRIMARY 4 NULL 6 Using index
t3 eq_ref PRIMARY PRIMARY 2 t1.gid 1 where used
table type possible_keys key key_len ref rows Extra
t1 index PRIMARY PRIMARY 4 NULL 6 Using index; Using temporary; Using filesort
t2 eq_ref PRIMARY,uid PRIMARY 4 t1.gid 1
t3 eq_ref PRIMARY PRIMARY 2 t2.uid 1 where used; Using index
table type possible_keys key key_len ref rows Extra
t1 index PRIMARY PRIMARY 4 NULL 6 Using index; Using temporary; Using filesort
t3 eq_ref PRIMARY PRIMARY 2 t1.gid 1 where used
table type possible_keys key key_len ref rows Extra
t1 ALL NULL NULL NULL NULL 6 Using temporary; Using filesort
t3 eq_ref PRIMARY PRIMARY 2 t1.skr 1 where used
mysql-test/t/order_by.test
View file @
1731161f
...
...
@@ -168,8 +168,8 @@ drop table t1,t2,t3;
#bug reported by Wouter de Jong
drop
table
if
exists
members
;
CREATE
TABLE
members
(
drop
table
if
exists
t1
;
CREATE
TABLE
t1
(
member_id
int
(
11
)
NOT
NULL
auto_increment
,
inschrijf_datum
varchar
(
20
)
NOT
NULL
default
''
,
lastchange_datum
varchar
(
20
)
NOT
NULL
default
''
,
...
...
@@ -200,8 +200,50 @@ CREATE TABLE members (
PRIMARY
KEY
(
member_id
)
)
TYPE
=
MyISAM
PACK_KEYS
=
1
;
insert
into
members
(
member_id
)
values
(
1
),(
2
),(
3
);
select
member_id
,
nickname
,
voornaam
FROM
members
insert
into
t1
(
member_id
)
values
(
1
),(
2
),(
3
);
select
member_id
,
nickname
,
voornaam
FROM
t1
ORDER
by
lastchange_datum
DESC
LIMIT
2
;
drop
table
members
;
drop
table
t1
;
#
# Test optimizing bug with EQ_REF tables, where some ORDER BY parts where
# wrongly removed.
CREATE
TABLE
t1
(
gid
int
(
10
)
unsigned
NOT
NULL
auto_increment
,
cid
smallint
(
5
)
unsigned
NOT
NULL
default
'0'
,
PRIMARY
KEY
(
gid
),
KEY
component_id
(
cid
)
)
TYPE
=
MyISAM
;
INSERT
INTO
t1
VALUES
(
103853
,
108
),(
103867
,
108
),(
103962
,
108
),(
104505
,
108
),(
104619
,
108
),(
104620
,
108
);
ALTER
TABLE
t1
add
skr
int
(
10
)
not
null
;
CREATE
TABLE
t2
(
gid
int
(
10
)
unsigned
NOT
NULL
default
'0'
,
uid
smallint
(
5
)
unsigned
NOT
NULL
default
'1'
,
sid
tinyint
(
3
)
unsigned
NOT
NULL
default
'1'
,
PRIMARY
KEY
(
gid
),
KEY
uid
(
uid
),
KEY
status_id
(
sid
)
)
TYPE
=
MyISAM
;
INSERT
INTO
t2
VALUES
(
103853
,
250
,
5
),(
103867
,
27
,
5
),(
103962
,
27
,
5
),(
104505
,
117
,
5
),(
104619
,
75
,
5
),(
104620
,
15
,
5
);
CREATE
TABLE
t3
(
uid
smallint
(
6
)
NOT
NULL
auto_increment
,
PRIMARY
KEY
(
uid
)
)
TYPE
=
MyISAM
;
INSERT
INTO
t3
VALUES
(
1
),(
15
),(
27
),(
75
),(
117
),(
250
);
ALTER
TABLE
t3
add
skr
int
(
10
)
not
null
;
select
t1
.
gid
,
t2
.
sid
,
t3
.
uid
from
t2
,
t1
,
t3
where
t2
.
gid
=
t1
.
gid
and
t2
.
uid
=
t3
.
uid
order
by
t3
.
uid
,
t1
.
gid
;
select
t1
.
gid
,
t2
.
sid
,
t3
.
uid
from
t3
,
t2
,
t1
where
t2
.
gid
=
t1
.
gid
and
t2
.
uid
=
t3
.
uid
order
by
t3
.
uid
,
t1
.
gid
;
# The following ORDER BY can be optimimized
EXPLAIN
select
t1
.
gid
,
t2
.
sid
,
t3
.
uid
from
t3
,
t2
,
t1
where
t2
.
gid
=
t1
.
gid
and
t2
.
uid
=
t3
.
uid
order
by
t1
.
gid
,
t3
.
uid
;
EXPLAIN
SELECT
t1
.
gid
,
t3
.
uid
from
t1
,
t3
where
t1
.
gid
=
t3
.
uid
order
by
t1
.
gid
,
t3
.
skr
;
# The following ORDER BY can't be optimimized
EXPLAIN
SELECT
t1
.
gid
,
t2
.
sid
,
t3
.
uid
from
t2
,
t1
,
t3
where
t2
.
gid
=
t1
.
gid
and
t2
.
uid
=
t3
.
uid
order
by
t3
.
uid
,
t1
.
gid
;
EXPLAIN
SELECT
t1
.
gid
,
t3
.
uid
from
t1
,
t3
where
t1
.
gid
=
t3
.
uid
order
by
t3
.
skr
,
t1
.
gid
;
EXPLAIN
SELECT
t1
.
gid
,
t3
.
uid
from
t1
,
t3
where
t1
.
skr
=
t3
.
uid
order
by
t1
.
gid
,
t3
.
skr
;
drop
table
t1
,
t2
,
t3
;
mysys/default.c
View file @
1731161f
...
...
@@ -222,7 +222,7 @@ static my_bool search_default_file(DYNAMIC_ARRAY *args, MEM_ROOT *alloc,
const
char
*
dir
,
const
char
*
config_file
,
const
char
*
ext
,
TYPELIB
*
group
)
{
char
name
[
FN_REFLEN
+
10
],
buff
[
FN_REFLEN
+
1
],
*
ptr
,
*
end
,
*
value
,
*
tmp
;
char
name
[
FN_REFLEN
+
10
],
buff
[
4096
],
*
ptr
,
*
end
,
*
value
,
*
tmp
;
FILE
*
fp
;
uint
line
=
0
;
my_bool
read_values
=
0
,
found_group
=
0
;
...
...
sql/sql_select.cc
View file @
1731161f
...
...
@@ -2649,12 +2649,12 @@ static void update_depend_map(JOIN *join)
for
(
i
=
0
;
i
<
ref
->
key_parts
;
i
++
,
item
++
)
depend_map
|=
(
*
item
)
->
used_tables
();
ref
->
depend_map
=
depend_map
;
for
(
JOIN_TAB
*
join_tab2
=
join
->
join_tab
;
for
(
JOIN_TAB
*
*
tab
=
join
->
map2table
;
depend_map
;
join_tab2
++
,
depend_map
>>=
1
)
tab
++
,
depend_map
>>=
1
)
{
if
(
depend_map
&
1
)
ref
->
depend_map
|=
join_tab2
->
ref
.
depend_map
;
ref
->
depend_map
|=
(
*
tab
)
->
ref
.
depend_map
;
}
}
}
...
...
@@ -2671,12 +2671,12 @@ static void update_depend_map(JOIN *join, ORDER *order)
order
->
depend_map
=
depend_map
=
order
->
item
[
0
]
->
used_tables
();
if
(
!
(
order
->
depend_map
&
RAND_TABLE_BIT
))
// Not item_sum() or RAND()
{
for
(
JOIN_TAB
*
join_tab
=
join
->
join_tab
;
for
(
JOIN_TAB
*
*
tab
=
join
->
map2table
;
depend_map
;
join_
tab
++
,
depend_map
>>=
1
)
tab
++
,
depend_map
>>=
1
)
{
if
(
depend_map
&
1
)
order
->
depend_map
|=
join_tab
->
ref
.
depend_map
;
order
->
depend_map
|=
(
*
tab
)
->
ref
.
depend_map
;
}
}
}
...
...
Write
Preview
Markdown
is supported
0%
Try again
or
attach a new file
Attach a file
Cancel
You are about to add
0
people
to the discussion. Proceed with caution.
Finish editing this message first!
Cancel
Please
register
or
sign in
to comment