(mysql.info.gz) Reserved words

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 9.6 Treatment of Reserved Words in MySQL
 ========================================
 
 A common problem stems from trying to use an identifier such as a table
 or column name that is the name of a built-in MySQL data type or
 function, such as `TIMESTAMP' or `GROUP'.  You're allowed to do this
 (for example, `ABS' is allowed as a column name). However, by default,
 no whitespace is allowed in function invocations between the function
 name and the following `(' character. This requirement allows a
 function call to be distinguished from a reference to a column name.
 
 A side effect of this behavior is that omitting a space in some contexts
 causes an identifier to be interpreted as a function name. For example,
 this statement is legal:
 
      mysql> CREATE TABLE abs (val INT);
 
 But omitting the space after `abs' causes a syntax error because the
 statement then appears to invoke the `ABS()' function:
 
      mysql> CREATE TABLE abs(val INT);
 
 If the server SQL mode includes the `IGNORE_SPACE' mode value, the
 server allows function invocations to have whitespace between a function
 name and the following `(' character. This causes function names to be
 treated as reserved words. As a result, identifiers that are the same as
 function names must be quoted as described in  Legal names.  The
 server SQL mode is controlled as described in  Server SQL mode.
 
 The words in the following table are explicitly reserved in MySQL. Most
 of them are forbidden by standard SQL as column and/or table names (for
 example, `GROUP').  A few are reserved because MySQL needs them and
 (currently) uses a `yacc' parser.  A reserved word can be used as an
 identifier if you quote it.
 
 *Word*                   *Word*                   *Word*
 `ADD'                    `ALL'                    `ALTER'
 `ANALYZE'                `AND'                    `AS'
 `ASC'                    `ASENSITIVE'             `BEFORE'
 `BETWEEN'                `BIGINT'                 `BINARY'
 `BLOB'                   `BOTH'                   `BY'
 `CALL'                   `CASCADE'                `CASE'
 `CHANGE'                 `CHAR'                   `CHARACTER'
 `CHECK'                  `COLLATE'                `COLUMN'
 `CONDITION'              `CONNECTION'             `CONSTRAINT'
 `CONTINUE'               `CONVERT'                `CREATE'
 `CROSS'                  `CURRENT_DATE'           `CURRENT_TIME'
 `CURRENT_TIMESTAMP'      `CURRENT_USER'           `CURSOR'
 `DATABASE'               `DATABASES'              `DAY_HOUR'
 `DAY_MICROSECOND'        `DAY_MINUTE'             `DAY_SECOND'
 `DEC'                    `DECIMAL'                `DECLARE'
 `DEFAULT'                `DELAYED'                `DELETE'
 `DESC'                   `DESCRIBE'               `DETERMINISTIC'
 `DISTINCT'               `DISTINCTROW'            `DIV'
 `DOUBLE'                 `DROP'                   `DUAL'
 `EACH'                   `ELSE'                   `ELSEIF'
 `ENCLOSED'               `ESCAPED'                `EXISTS'
 `EXIT'                   `EXPLAIN'                `FALSE'
 `FETCH'                  `FLOAT'                  `FOR'
 `FORCE'                  `FOREIGN'                `FROM'
 `FULLTEXT'               `GOTO'                   `GRANT'
 `GROUP'                  `HAVING'                 `HIGH_PRIORITY'
 `HOUR_MICROSECOND'       `HOUR_MINUTE'            `HOUR_SECOND'
 `IF'                     `IGNORE'                 `IN'
 `INDEX'                  `INFILE'                 `INNER'
 `INOUT'                  `INSENSITIVE'            `INSERT'
 `INT'                    `INTEGER'                `INTERVAL'
 `INTO'                   `IS'                     `ITERATE'
 `JOIN'                   `KEY'                    `KEYS'
 `KILL'                   `LEADING'                `LEAVE'
 `LEFT'                   `LIKE'                   `LIMIT'
 `LINES'                  `LOAD'                   `LOCALTIME'
 `LOCALTIMESTAMP'         `LOCK'                   `LONG'
 `LONGBLOB'               `LONGTEXT'               `LOOP'
 `LOW_PRIORITY'           `MATCH'                  `MEDIUMBLOB'
 `MEDIUMINT'              `MEDIUMTEXT'             `MIDDLEINT'
 `MINUTE_MICROSECOND'     `MINUTE_SECOND'          `MOD'
 `MODIFIES'               `NATURAL'                `NOT'
 `NO_WRITE_TO_BINLOG'     `NULL'                   `NUMERIC'
 `ON'                     `OPTIMIZE'               `OPTION'
 `OPTIONALLY'             `OR'                     `ORDER'
 `OUT'                    `OUTER'                  `OUTFILE'
 `PRECISION'              `PRIMARY'                `PROCEDURE'
 `PURGE'                  `READ'                   `READS'
 `REAL'                   `REFERENCES'             `REGEXP'
 `RENAME'                 `REPEAT'                 `REPLACE'
 `REQUIRE'                `RESTRICT'               `RETURN'
 `REVOKE'                 `RIGHT'                  `RLIKE'
 `SCHEMA'                 `SCHEMAS'                `SECOND_MICROSECOND'
 `SELECT'                 `SENSITIVE'              `SEPARATOR'
 `SET'                    `SHOW'                   `SMALLINT'
 `SONAME'                 `SPATIAL'                `SPECIFIC'
 `SQL'                    `SQLEXCEPTION'           `SQLSTATE'
 `SQLWARNING'             `SQL_BIG_RESULT'         `SQL_CALC_FOUND_ROWS'
 `SQL_SMALL_RESULT'       `SSL'                    `STARTING'
 `STRAIGHT_JOIN'          `TABLE'                  `TERMINATED'
 `THEN'                   `TINYBLOB'               `TINYINT'
 `TINYTEXT'               `TO'                     `TRAILING'
 `TRIGGER'                `TRUE'                   `UNDO'
 `UNION'                  `UNIQUE'                 `UNLOCK'
 `UNSIGNED'               `UPDATE'                 `USAGE'
 `USE'                    `USING'                  `UTC_DATE'
 `UTC_TIME'               `UTC_TIMESTAMP'          `VALUES'
 `VARBINARY'              `VARCHAR'                `VARCHARACTER'
 `VARYING'                `WHEN'                   `WHERE'
 `WHILE'                  `WITH'                   `WRITE'
 `XOR'                    `YEAR_MONTH'             `ZEROFILL'
 
 MySQL allows some keywords to be used as unquoted identifiers because
 many people previously used them.  Examples are those in the following
 list:
 
    * `ACTION'
 
    * `BIT'
 
    * `DATE'
 
    * `ENUM'
 
    * `NO'
 
    * `TEXT'
 
    * `TIME'
 
    * `TIMESTAMP'
 

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