/****************************************************** Interface between Innobase row operations and MySQL. Contains also create table and other data dictionary operations. (c) 2000 Innobase Oy Created 9/17/2000 Heikki Tuuri *******************************************************/ #ifndef row0mysql_h #define row0mysql_h #include "univ.i" #include "data0data.h" #include "que0types.h" #include "dict0types.h" #include "trx0types.h" #include "row0types.h" #include "btr0pcur.h" #include "trx0types.h" typedef struct row_prebuilt_struct row_prebuilt_t; /*********************************************************************** Frees the blob heap in prebuilt when no longer needed. */ void row_mysql_prebuilt_free_blob_heap( /*==============================*/ row_prebuilt_t* prebuilt); /* in: prebuilt struct of a ha_innobase:: table handle */ /*********************************************************************** Stores a >= 5.0.3 format true VARCHAR length to dest, in the MySQL row format. */ byte* row_mysql_store_true_var_len( /*=========================*/ /* out: pointer to the data, we skip the 1 or 2 bytes at the start that are used to store the len */ byte* dest, /* in: where to store */ ulint len, /* in: length, must fit in two bytes */ ulint lenlen);/* in: storage length of len: either 1 or 2 bytes */ /*********************************************************************** Reads a >= 5.0.3 format true VARCHAR length, in the MySQL row format, and returns a pointer to the data. */ byte* row_mysql_read_true_varchar( /*========================*/ /* out: pointer to the data, we skip the 1 or 2 bytes at the start that are used to store the len */ ulint* len, /* out: variable-length field length */ byte* field, /* in: field in the MySQL format */ ulint lenlen);/* in: storage length of len: either 1 or 2 bytes */ /*********************************************************************** Stores a reference to a BLOB in the MySQL format. */ void row_mysql_store_blob_ref( /*=====================*/ byte* dest, /* in: where to store */ ulint col_len, /* in: dest buffer size: determines into how many bytes the BLOB length is stored, this may vary from 1 to 4 bytes */ byte* data, /* in: BLOB data */ ulint len); /* in: BLOB length */ /*********************************************************************** Reads a reference to a BLOB in the MySQL format. */ byte* row_mysql_read_blob_ref( /*====================*/ /* out: pointer to BLOB data */ ulint* len, /* out: BLOB length */ byte* ref, /* in: BLOB reference in the MySQL format */ ulint col_len); /* in: BLOB reference length (not BLOB length) */ /****************************************************************** Stores a non-SQL-NULL field given in the MySQL format in the InnoDB format. The counterpart of this function is row_sel_field_store_in_mysql_format() in row0sel.c. */ byte* row_mysql_store_col_in_innobase_format( /*===================================*/ /* out: up to which byte we used buf in the conversion */ dfield_t* dfield, /* in/out: dfield where dtype information must be already set when this function is called! */ byte* buf, /* in/out: buffer for a converted integer value; this must be at least col_len long then! */ ibool row_format_col, /* TRUE if the mysql_data is from a MySQL row, FALSE if from a MySQL key value; in MySQL, a true VARCHAR storage format differs in a row and in a key value: in a key value the length is always stored in 2 bytes! */ byte* mysql_data, /* in: MySQL column value, not SQL NULL; NOTE that dfield may also get a pointer to mysql_data, therefore do not discard this as long as dfield is used! */ ulint col_len, /* in: MySQL column length; NOTE that this is the storage length of the column in the MySQL format row, not necessarily the length of the actual payload data; if the column is a true VARCHAR then this is irrelevant */ ulint comp); /* in: nonzero=compact format */ /******************************************************************** Handles user errors and lock waits detected by the database engine. */ ibool row_mysql_handle_errors( /*====================*/ /* out: TRUE if it was a lock wait and we should continue running the query thread */ ulint* new_err,/* out: possible new error encountered in rollback, or the old error which was during the function entry */ trx_t* trx, /* in: transaction */ que_thr_t* thr, /* in: query thread */ trx_savept_t* savept);/* in: savepoint */ /************************************************************************ Create a prebuilt struct for a MySQL table handle. */ row_prebuilt_t* row_create_prebuilt( /*================*/ /* out, own: a prebuilt struct */ dict_table_t* table); /* in: Innobase table handle */ /************************************************************************ Free a prebuilt struct for a MySQL table handle. */ void row_prebuilt_free( /*==============*/ row_prebuilt_t* prebuilt); /* in, own: prebuilt struct */ /************************************************************************* Updates the transaction pointers in query graphs stored in the prebuilt struct. */ void row_update_prebuilt_trx( /*====================*/ /* out: prebuilt dtuple */ row_prebuilt_t* prebuilt, /* in: prebuilt struct in MySQL handle */ trx_t* trx); /* in: transaction handle */ /************************************************************************* Unlocks an AUTO_INC type lock possibly reserved by trx. */ void row_unlock_table_autoinc_for_mysql( /*===============================*/ trx_t* trx); /* in: transaction */ /************************************************************************* Sets an AUTO_INC type lock on the table mentioned in prebuilt. The AUTO_INC lock gives exclusive access to the auto-inc counter of the table. The lock is reserved only for the duration of an SQL statement. It is not compatible with another AUTO_INC or exclusive lock on the table. */ int row_lock_table_autoinc_for_mysql( /*=============================*/ /* out: error code or DB_SUCCESS */ row_prebuilt_t* prebuilt); /* in: prebuilt struct in the MySQL table handle */ /************************************************************************* Sets a table lock on the table mentioned in prebuilt. */ int row_lock_table_for_mysql( /*=====================*/ /* out: error code or DB_SUCCESS */ row_prebuilt_t* prebuilt, /* in: prebuilt struct in the MySQL table handle */ dict_table_t* table, /* in: table to lock, or NULL if prebuilt->table should be locked as prebuilt->select_lock_type */ ulint mode); /* in: lock mode of table (ignored if table==NULL) */ /************************************************************************* Does an insert for MySQL. */ int row_insert_for_mysql( /*=================*/ /* out: error code or DB_SUCCESS */ byte* mysql_rec, /* in: row in the MySQL format */ row_prebuilt_t* prebuilt); /* in: prebuilt struct in MySQL handle */ /************************************************************************* Builds a dummy query graph used in selects. */ void row_prebuild_sel_graph( /*===================*/ row_prebuilt_t* prebuilt); /* in: prebuilt struct in MySQL handle */ /************************************************************************* Gets pointer to a prebuilt update vector used in updates. If the update graph has not yet been built in the prebuilt struct, then this function first builds it. */ upd_t* row_get_prebuilt_update_vector( /*===========================*/ /* out: prebuilt update vector */ row_prebuilt_t* prebuilt); /* in: prebuilt struct in MySQL handle */ /************************************************************************* Checks if a table is such that we automatically created a clustered index on it (on row id). */ ibool row_table_got_default_clust_index( /*==============================*/ dict_table_t* table); /************************************************************************* Calculates the key number used inside MySQL for an Innobase index. We have to take into account if we generated a default clustered index for the table */ ulint row_get_mysql_key_number_for_index( /*===============================*/ dict_index_t* index); /************************************************************************* Does an update or delete of a row for MySQL. */ int row_update_for_mysql( /*=================*/ /* out: error code or DB_SUCCESS */ byte* mysql_rec, /* in: the row to be updated, in the MySQL format */ row_prebuilt_t* prebuilt); /* in: prebuilt struct in MySQL handle */ /************************************************************************* This can only be used when srv_locks_unsafe_for_binlog is TRUE. Before calling this function we must use trx_reset_new_rec_lock_info() and trx_register_new_rec_lock() to store the information which new record locks really were set. This function removes a newly set lock under prebuilt->pcur, and also under prebuilt->clust_pcur. Currently, this is only used and tested in the case of an UPDATE or a DELETE statement, where the row lock is of the LOCK_X type. Thus, this implements a 'mini-rollback' that releases the latest record locks we set. */ int row_unlock_for_mysql( /*=================*/ /* out: error code or DB_SUCCESS */ row_prebuilt_t* prebuilt, /* in: prebuilt struct in MySQL handle */ ibool has_latches_on_recs);/* TRUE if called so that we have the latches on the records under pcur and clust_pcur, and we do not need to reposition the cursors. */ /************************************************************************* Creates an query graph node of 'update' type to be used in the MySQL interface. */ upd_node_t* row_create_update_node_for_mysql( /*=============================*/ /* out, own: update node */ dict_table_t* table, /* in: table to update */ mem_heap_t* heap); /* in: mem heap from which allocated */ /************************************************************************** Does a cascaded delete or set null in a foreign key operation. */ ulint row_update_cascade_for_mysql( /*=========================*/ /* out: error code or DB_SUCCESS */ que_thr_t* thr, /* in: query thread */ upd_node_t* node, /* in: update node used in the cascade or set null operation */ dict_table_t* table); /* in: table where we do the operation */ /************************************************************************* Locks the data dictionary exclusively for performing a table create or other data dictionary modification operation. */ void row_mysql_lock_data_dictionary( /*===========================*/ trx_t* trx); /* in: transaction */ /************************************************************************* Unlocks the data dictionary exclusive lock. */ void row_mysql_unlock_data_dictionary( /*=============================*/ trx_t* trx); /* in: transaction */ /************************************************************************* Locks the data dictionary in shared mode from modifications, for performing foreign key check, rollback, or other operation invisible to MySQL. */ void row_mysql_freeze_data_dictionary( /*=============================*/ trx_t* trx); /* in: transaction */ /************************************************************************* Unlocks the data dictionary shared lock. */ void row_mysql_unfreeze_data_dictionary( /*===============================*/ trx_t* trx); /* in: transaction */ /************************************************************************* Does a table creation operation for MySQL. If the name of the created table ends to characters INNODB_MONITOR, then this also starts printing of monitor output by the master thread. */ int row_create_table_for_mysql( /*=======================*/ /* out: error code or DB_SUCCESS */ dict_table_t* table, /* in: table definition */ trx_t* trx); /* in: transaction handle */ /************************************************************************* Does an index creation operation for MySQL. TODO: currently failure to create an index results in dropping the whole table! This is no problem currently as all indexes must be created at the same time as the table. */ int row_create_index_for_mysql( /*=======================*/ /* out: error number or DB_SUCCESS */ dict_index_t* index, /* in: index definition */ trx_t* trx, /* in: transaction handle */ const ulint* field_lengths); /* in: if not NULL, must contain dict_index_get_n_fields(index) actual field lengths for the index columns, which are then checked for not being too large. */ /************************************************************************* Scans a table create SQL string and adds to the data dictionary the foreign key constraints declared in the string. This function should be called after the indexes for a table have been created. Each foreign key constraint must be accompanied with indexes in bot participating tables. The indexes are allowed to contain more fields than mentioned in the constraint. */ int row_table_add_foreign_constraints( /*==============================*/ /* out: error code or DB_SUCCESS */ trx_t* trx, /* in: transaction */ const char* sql_string, /* in: table create statement where foreign keys are declared like: FOREIGN KEY (a, b) REFERENCES table2(c, d), table2 can be written also with the database name before it: test.table2 */ const char* name, /* in: table full name in the normalized form database_name/table_name */ ibool reject_fks); /* in: if TRUE, fail with error code DB_CANNOT_ADD_CONSTRAINT if any foreign keys are found. */ /************************************************************************* The master thread in srv0srv.c calls this regularly to drop tables which we must drop in background after queries to them have ended. Such lazy dropping of tables is needed in ALTER TABLE on Unix. */ ulint row_drop_tables_for_mysql_in_background(void); /*=========================================*/ /* out: how many tables dropped + remaining tables in list */ /************************************************************************* Get the background drop list length. NOTE: the caller must own the kernel mutex! */ ulint row_get_background_drop_list_len_low(void); /*======================================*/ /* out: how many tables in list */ /************************************************************************* Truncates a table for MySQL. */ int row_truncate_table_for_mysql( /*=========================*/ /* out: error code or DB_SUCCESS */ dict_table_t* table, /* in: table handle */ trx_t* trx); /* in: transaction handle */ /************************************************************************* Drops a table for MySQL. If the name of the dropped table ends to characters INNODB_MONITOR, then this also stops printing of monitor output by the master thread. */ int row_drop_table_for_mysql( /*=====================*/ /* out: error code or DB_SUCCESS */ const char* name, /* in: table name */ trx_t* trx, /* in: transaction handle */ ibool drop_db);/* in: TRUE=dropping whole database */ /************************************************************************* Discards the tablespace of a table which stored in an .ibd file. Discarding means that this function deletes the .ibd file and assigns a new table id for the table. Also the flag table->ibd_file_missing is set TRUE. */ int row_discard_tablespace_for_mysql( /*=============================*/ /* out: error code or DB_SUCCESS */ const char* name, /* in: table name */ trx_t* trx); /* in: transaction handle */ /********************************************************************* Imports a tablespace. The space id in the .ibd file must match the space id of the table in the data dictionary. */ int row_import_tablespace_for_mysql( /*============================*/ /* out: error code or DB_SUCCESS */ const char* name, /* in: table name */ trx_t* trx); /* in: transaction handle */ /************************************************************************* Drops a database for MySQL. */ int row_drop_database_for_mysql( /*========================*/ /* out: error code or DB_SUCCESS */ const char* name, /* in: database name which ends to '/' */ trx_t* trx); /* in: transaction handle */ /************************************************************************* Renames a table for MySQL. */ int row_rename_table_for_mysql( /*=======================*/ /* out: error code or DB_SUCCESS */ const char* old_name, /* in: old table name */ const char* new_name, /* in: new table name */ trx_t* trx); /* in: transaction handle */ /************************************************************************* Checks a table for corruption. */ ulint row_check_table_for_mysql( /*======================*/ /* out: DB_ERROR or DB_SUCCESS */ row_prebuilt_t* prebuilt); /* in: prebuilt struct in MySQL handle */ /* A struct describing a place for an individual column in the MySQL row format which is presented to the table handler in ha_innobase. This template struct is used to speed up row transformations between Innobase and MySQL. */ typedef struct mysql_row_templ_struct mysql_row_templ_t; struct mysql_row_templ_struct { ulint col_no; /* column number of the column */ ulint rec_field_no; /* field number of the column in an Innobase record in the current index; not defined if template_type is ROW_MYSQL_WHOLE_ROW */ ulint mysql_col_offset; /* offset of the column in the MySQL row format */ ulint mysql_col_len; /* length of the column in the MySQL row format */ ulint mysql_null_byte_offset; /* MySQL NULL bit byte offset in a MySQL record */ ulint mysql_null_bit_mask; /* bit mask to get the NULL bit, zero if column cannot be NULL */ ulint type; /* column type in Innobase mtype numbers DATA_CHAR... */ ulint mysql_type; /* MySQL type code; this is always < 256 */ ulint mysql_length_bytes; /* if mysql_type == DATA_MYSQL_TRUE_VARCHAR, this tells whether we should use 1 or 2 bytes to store the MySQL true VARCHAR data length at the start of row in the MySQL format (NOTE that the MySQL key value format always uses 2 bytes for the data len) */ ulint charset; /* MySQL charset-collation code of the column, or zero */ ulint mbminlen; /* minimum length of a char, in bytes, or zero if not a char type */ ulint mbmaxlen; /* maximum length of a char, in bytes, or zero if not a char type */ ulint is_unsigned; /* if a column type is an integer type and this field is != 0, then it is an unsigned integer type */ }; #define MYSQL_FETCH_CACHE_SIZE 8 /* After fetching this many rows, we start caching them in fetch_cache */ #define MYSQL_FETCH_CACHE_THRESHOLD 4 #define ROW_PREBUILT_ALLOCATED 78540783 #define ROW_PREBUILT_FREED 26423527 /* A struct for (sometimes lazily) prebuilt structures in an Innobase table handle used within MySQL; these are used to save CPU time. */ struct row_prebuilt_struct { ulint magic_n; /* this magic number is set to ROW_PREBUILT_ALLOCATED when created and to ROW_PREBUILT_FREED when the struct has been freed; used in debugging */ dict_table_t* table; /* Innobase table handle */ trx_t* trx; /* current transaction handle */ ibool sql_stat_start; /* TRUE when we start processing of an SQL statement: we may have to set an intention lock on the table, create a consistent read view etc. */ ibool mysql_has_locked; /* this is set TRUE when MySQL calls external_lock on this handle with a lock flag, and set FALSE when with the F_UNLOCK flag */ ibool clust_index_was_generated; /* if the user did not define a primary key in MySQL, then Innobase automatically generated a clustered index where the ordering column is the row id: in this case this flag is set to TRUE */ dict_index_t* index; /* current index for a search, if any */ ulint read_just_key; /* set to 1 when MySQL calls ha_innobase::extra with the argument HA_EXTRA_KEYREAD; it is enough to read just columns defined in the index (i.e., no read of the clustered index record necessary) */ ibool used_in_HANDLER;/* TRUE if we have been using this handle in a MySQL HANDLER low level index cursor command: then we must store the pcur position even in a unique search from a clustered index, because HANDLER allows NEXT and PREV in such a situation */ ulint template_type; /* ROW_MYSQL_WHOLE_ROW, ROW_MYSQL_REC_FIELDS, ROW_MYSQL_DUMMY_TEMPLATE, or ROW_MYSQL_NO_TEMPLATE */ ulint n_template; /* number of elements in the template */ ulint null_bitmap_len;/* number of bytes in the SQL NULL bitmap at the start of a row in the MySQL format */ ibool need_to_access_clustered; /* if we are fetching columns through a secondary index and at least one column is not in the secondary index, then this is set to TRUE */ ibool templ_contains_blob;/* TRUE if the template contains BLOB column(s) */ mysql_row_templ_t* mysql_template;/* template used to transform rows fast between MySQL and Innobase formats; memory for this template is not allocated from 'heap' */ mem_heap_t* heap; /* memory heap from which these auxiliary structures are allocated when needed */ ins_node_t* ins_node; /* Innobase SQL insert node used to perform inserts to the table */ byte* ins_upd_rec_buff;/* buffer for storing data converted to the Innobase format from the MySQL format */ ulint hint_need_to_fetch_extra_cols; /* normally this is set to 0; if this is set to ROW_RETRIEVE_PRIMARY_KEY, then we should at least retrieve all columns in the primary key; if this is set to ROW_RETRIEVE_ALL_COLS, then we must retrieve all columns in the key (if read_just_key == 1), or all columns in the table */ upd_node_t* upd_node; /* Innobase SQL update node used to perform updates and deletes */ que_fork_t* ins_graph; /* Innobase SQL query graph used in inserts */ que_fork_t* upd_graph; /* Innobase SQL query graph used in updates or deletes */ btr_pcur_t* pcur; /* persistent cursor used in selects and updates */ btr_pcur_t* clust_pcur; /* persistent cursor used in some selects and updates */ que_fork_t* sel_graph; /* dummy query graph used in selects */ dtuple_t* search_tuple; /* prebuilt dtuple used in selects */ byte row_id[DATA_ROW_ID_LEN]; /* if the clustered index was generated, the row id of the last row fetched is stored here */ dtuple_t* clust_ref; /* prebuilt dtuple used in sel/upd/del */ ulint select_lock_type;/* LOCK_NONE, LOCK_S, or LOCK_X */ ulint stored_select_lock_type;/* this field is used to remember the original select_lock_type that was decided in ha_innodb.cc, ::store_lock(), ::external_lock(), etc. */ ulint row_read_type; /* ROW_READ_WITH_LOCKS if row locks should be the obtained for records under an UPDATE or DELETE cursor. If innodb_locks_unsafe_for_binlog is TRUE, this can be set to ROW_READ_TRY_SEMI_CONSISTENT, so that if the row under an UPDATE or DELETE cursor was locked by another transaction, InnoDB will resort to reading the last committed value ('semi-consistent read'). Then, this field will be set to ROW_READ_DID_SEMI_CONSISTENT to indicate that. If the row does not match the WHERE condition, MySQL will invoke handler::unlock_row() to clear the flag back to ROW_READ_TRY_SEMI_CONSISTENT and to simply skip the row. If the row matches, the next call to row_search_for_mysql() will lock the row. This eliminates lock waits in some cases; note that this breaks serializability. */ ulint mysql_prefix_len;/* byte offset of the end of the last requested column */ ulint mysql_row_len; /* length in bytes of a row in the MySQL format */ ulint n_rows_fetched; /* number of rows fetched after positioning the current cursor */ ulint fetch_direction;/* ROW_SEL_NEXT or ROW_SEL_PREV */ byte* fetch_cache[MYSQL_FETCH_CACHE_SIZE]; /* a cache for fetched rows if we fetch many rows from the same cursor: it saves CPU time to fetch them in a batch; we reserve mysql_row_len bytes for each such row; these pointers point 4 bytes past the allocated mem buf start, because there is a 4 byte magic number at the start and at the end */ ibool keep_other_fields_on_keyread; /* when using fetch cache with HA_EXTRA_KEYREAD, don't overwrite other fields in mysql row row buffer.*/ ulint fetch_cache_first;/* position of the first not yet fetched row in fetch_cache */ ulint n_fetch_cached; /* number of not yet fetched rows in fetch_cache */ mem_heap_t* blob_heap; /* in SELECTS BLOB fie lds are copied to this heap */ mem_heap_t* old_vers_heap; /* memory heap where a previous version is built in consistent read */ ulint magic_n2; /* this should be the same as magic_n */ }; #define ROW_PREBUILT_FETCH_MAGIC_N 465765687 #define ROW_MYSQL_WHOLE_ROW 0 #define ROW_MYSQL_REC_FIELDS 1 #define ROW_MYSQL_NO_TEMPLATE 2 #define ROW_MYSQL_DUMMY_TEMPLATE 3 /* dummy template used in row_scan_and_check_index */ /* Values for hint_need_to_fetch_extra_cols */ #define ROW_RETRIEVE_PRIMARY_KEY 1 #define ROW_RETRIEVE_ALL_COLS 2 /* Values for row_read_type */ #define ROW_READ_WITH_LOCKS 0 #define ROW_READ_TRY_SEMI_CONSISTENT 1 #define ROW_READ_DID_SEMI_CONSISTENT 2 #ifndef UNIV_NONINL #include "row0mysql.ic" #endif #endif