Fix for BUG#10491: Server returns data as charset binary

SHOW CREATE TABLE or SELECT FROM I_S.

Actually, the bug discovers two problems:
  - the original query is not preserved properly. This is the problem
    of BUG#16291;
  - the resultset of SHOW CREATE TABLE statement is binary.

This patch fixes the second problem for the 5.0.

Both problems will be fixed in 5.1.


mysql-test/r/show_check.result:
  Update result file.
mysql-test/t/show_check.test:
  Provide test case for BUG#10491.
sql/item.h:
  Use utf8_general_ci instead of binary collation by default,
  because for views and base tables utf8 is the character set
  in which their definition is stored. For system constants
  it's the default character set, and for other objects
  (routines, triggers), no character set is stored, and
  therefore no character set is known, so returning utf8
  is just as good as any non-binary character set.
  This latter problem is fixed in 5.1 by 16291. In 5.1
  we will return the "real" character set.

mysql-test/t/show_check.test

@@ -18,6 +18,12 @@ flush privileges;
 
 create table t1 (a int not null primary key, b int not null,c int not null, key(b,c));
 insert into t1 values (1,2,2),(2,2,3),(3,2,4),(4,2,4);
+
+--echo -- Here we enable metadata just to check that the collation of the
+--echo -- resultset is non-binary for string type. This should be changed
+--echo -- after Bug#29394 is implemented.
+
+--enable_metadata
 check table t1 fast;
 check table t1 fast;
 check table t1 changed;
@@ -26,28 +32,58 @@ check table t1 changed;
 check table t1 medium;
 check table t1 extended;
 show index from t1;
+--disable_metadata
 --error 1062
 insert into t1 values (5,5,5);
+
+--echo -- Here we enable metadata just to check that the collation of the
+--echo -- resultset is non-binary for string type. This should be changed
+--echo -- after Bug#29394 is implemented.
+
+--enable_metadata
 optimize table t1;
+--disable_metadata
 optimize table t1;
 drop table t1;
 
 #show variables;
+
+--echo -- Here we enable metadata just to check that the collation of the
+--echo -- resultset is non-binary for string type. This should be changed
+--echo -- after Bug#29394 is implemented.
+
+--enable_metadata
 show variables like "wait_timeout%";
 show variables like "WAIT_timeout%";
 show variables like "this_doesn't_exists%";
 show table status from test like "this_doesn't_exists%";
 show databases;
 show databases like "test%";
+--disable_metadata
 
 #
 # Check of show index
 #
 create table t1 (f1 int not null, f2 int not null, f3 int not null, f4 int not null, primary key(f1,f2,f3,f4));
 insert into t1 values (1,1,1,0),(1,1,2,0),(1,1,3,0),(1,2,1,0),(1,2,2,0),(1,2,3,0),(1,3,1,0),(1,3,2,0),(1,3,3,0),(1,1,1,1),(1,1,2,1),(1,1,3,1),(1,2,1,1),(1,2,2,1),(1,2,3,1),(1,3,1,1),(1,3,2,1),(1,3,3,1);
+
+--echo -- Here we enable metadata just to check that the collation of the
+--echo -- resultset is non-binary for string type. This should be changed
+--echo -- after Bug#29394 is implemented.
+
+--enable_metadata
 analyze table t1;
+--disable_metadata
 show index from t1;
+
+--echo -- Here we enable metadata just to check that the collation of the
+--echo -- resultset is non-binary for string type. This should be changed
+--echo -- after Bug#29394 is implemented.
+
+--enable_metadata
+
 repair table t1;
+--disable_metadata
 show index from t1;
 drop table t1;
 
@@ -518,4 +554,216 @@ show status like 'slow_queries';
 select 1 from information_schema.tables limit 1;
 show status like 'slow_queries';
 
+#
+# BUG#10491: Server returns data as charset binary SHOW CREATE TABLE or SELECT
+# FROM I_S.
+#
+
+# Ensure that all needed objects are dropped.
+
+--disable_warnings
+DROP DATABASE IF EXISTS mysqltest1;
+DROP TABLE IF EXISTS t1;
+DROP VIEW IF EXISTS v1;
+DROP PROCEDURE IF EXISTS p1;
+DROP FUNCTION IF EXISTS f1;
+--enable_warnings
+
+# Create objects.
+
+CREATE DATABASE mysqltest1;
+
+CREATE TABLE t1(c INT NOT NULL PRIMARY KEY);
+
+CREATE TRIGGER t1_bi BEFORE INSERT ON t1 FOR EACH ROW SET @a = 1;
+
+CREATE VIEW v1 AS SELECT 1;
+
+CREATE PROCEDURE p1() SELECT 1;
+
+CREATE FUNCTION f1() RETURNS INT RETURN 1;
+
+
+# Test.
+
+set names utf8;
+
+--echo -- Here we enable metadata just to check that the collation of the
+--echo -- resultset is non-binary for string type. This should be changed
+--echo -- after Bug#29394 is implemented.
+
+--enable_metadata
+
+--echo ----------------------------------------------------------------
+
+SHOW CHARACTER SET LIKE 'utf8';
+
+--echo ----------------------------------------------------------------
+
+SHOW COLLATION LIKE 'latin1_bin';
+
+--echo ----------------------------------------------------------------
+
+SHOW CREATE DATABASE mysqltest1;
+
+--echo ----------------------------------------------------------------
+
+SHOW DATABASES LIKE 'mysqltest1';
+
+--echo ----------------------------------------------------------------
+
+SHOW CREATE TABLE t1;
+
+--echo ----------------------------------------------------------------
+
+SHOW INDEX FROM t1;
+
+--echo ----------------------------------------------------------------
+
+SELECT
+  TABLE_CATALOG,
+  TABLE_SCHEMA,
+  TABLE_NAME,
+  TABLE_TYPE,
+  ENGINE,
+  ROW_FORMAT,
+  TABLE_COLLATION,
+  CREATE_OPTIONS,
+  TABLE_COMMENT
+FROM INFORMATION_SCHEMA.TABLES
+WHERE table_name = 't1';
+
+--echo ----------------------------------------------------------------
+
+SELECT
+  TABLE_CATALOG,
+  TABLE_SCHEMA,
+  TABLE_NAME,
+  COLUMN_NAME,
+  COLUMN_DEFAULT,
+  IS_NULLABLE,
+  DATA_TYPE,
+  CHARACTER_SET_NAME,
+  COLLATION_NAME,
+  COLUMN_TYPE,
+  COLUMN_KEY,
+  EXTRA,
+  PRIVILEGES,
+  COLUMN_COMMENT
+FROM INFORMATION_SCHEMA.COLUMNS
+WHERE table_name = 't1';
+
+--echo ----------------------------------------------------------------
+
+SHOW TABLES LIKE 't1';
+
+--echo ----------------------------------------------------------------
+
+SHOW COLUMNS FROM t1;
+
+--echo ----------------------------------------------------------------
+
+SHOW TRIGGERS LIKE 't1';
+
+--echo ----------------------------------------------------------------
+
+SELECT 
+  TRIGGER_CATALOG,
+  TRIGGER_SCHEMA,
+  TRIGGER_NAME,
+  EVENT_MANIPULATION,
+  EVENT_OBJECT_CATALOG,
+  EVENT_OBJECT_SCHEMA,
+  EVENT_OBJECT_TABLE,
+  ACTION_CONDITION,
+  ACTION_STATEMENT,
+  ACTION_ORIENTATION,
+  ACTION_TIMING,
+  ACTION_REFERENCE_OLD_TABLE,
+  ACTION_REFERENCE_NEW_TABLE,
+  ACTION_REFERENCE_OLD_ROW,
+  ACTION_REFERENCE_NEW_ROW,
+  SQL_MODE,
+  DEFINER
+FROM INFORMATION_SCHEMA.TRIGGERS
+WHERE trigger_name = 't1_bi';
+
+--echo ----------------------------------------------------------------
+
+SHOW CREATE VIEW v1;
+
+--echo ----------------------------------------------------------------
+
+SELECT *
+FROM INFORMATION_SCHEMA.VIEWS
+WHERE table_name = 'v1';
+
+--echo ----------------------------------------------------------------
+
+SHOW CREATE PROCEDURE p1;
+
+--echo ----------------------------------------------------------------
+
+SELECT
+  SPECIFIC_NAME,
+  ROUTINE_CATALOG,
+  ROUTINE_SCHEMA,
+  ROUTINE_NAME,
+  ROUTINE_TYPE,
+  DTD_IDENTIFIER,
+  ROUTINE_BODY,
+  ROUTINE_DEFINITION,
+  EXTERNAL_NAME,
+  EXTERNAL_LANGUAGE,
+  PARAMETER_STYLE,
+  IS_DETERMINISTIC,
+  SQL_DATA_ACCESS,
+  SQL_PATH,
+  SECURITY_TYPE,
+  SQL_MODE,
+  ROUTINE_COMMENT,
+  DEFINER
+FROM INFORMATION_SCHEMA.ROUTINES
+WHERE routine_name = 'p1';
+
+--echo ----------------------------------------------------------------
+
+SHOW CREATE FUNCTION f1;
+
+--echo ----------------------------------------------------------------
+
+SELECT
+  SPECIFIC_NAME,
+  ROUTINE_CATALOG,
+  ROUTINE_SCHEMA,
+  ROUTINE_NAME,
+  ROUTINE_TYPE,
+  DTD_IDENTIFIER,
+  ROUTINE_BODY,
+  ROUTINE_DEFINITION,
+  EXTERNAL_NAME,
+  EXTERNAL_LANGUAGE,
+  PARAMETER_STYLE,
+  IS_DETERMINISTIC,
+  SQL_DATA_ACCESS,
+  SQL_PATH,
+  SECURITY_TYPE,
+  SQL_MODE,
+  ROUTINE_COMMENT,
+  DEFINER
+FROM INFORMATION_SCHEMA.ROUTINES
+WHERE routine_name = 'f1';
+
+--echo ----------------------------------------------------------------
+
+--disable_metadata
+
+# Cleanup.
+
+DROP DATABASE mysqltest1;
+DROP TABLE t1;
+DROP VIEW v1;
+DROP PROCEDURE p1;
+DROP FUNCTION f1;
+
 --echo End of 5.0 tests

sql/item.h

@@ -1764,11 +1764,17 @@ class Item_datetime :public Item_string
   enum_field_types field_type() const { return MYSQL_TYPE_DATETIME; }
 };
 
+/**
+  Item_empty_string -- is a utility class to put an item into List<Item>
+  which is then used in protocol.send_fields() when sending SHOW output to
+  the client.
+*/
+
 class Item_empty_string :public Item_string
 {
 public:
   Item_empty_string(const char *header,uint length, CHARSET_INFO *cs= NULL) :
-    Item_string("",0, cs ? cs : &my_charset_bin)
+    Item_string("",0, cs ? cs : &my_charset_utf8_general_ci)
     { name=(char*) header; max_length= cs ? length * cs->mbmaxlen : length; }
   void make_field(Send_field *field);
 };