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  • Introduction
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Keywords and Reserved Words

Keywords are words that have significance in SQL. Certain keywords, such as SELECT, UPDATE, or DELETE, are reserved and require special treatment for use as identifiers such as table and column names. For example, as table names, the reserved words must be quoted with backquotes:

mysql> CREATE TABLE select (a INT);
ERROR 1105 (HY000): line 0 column 19 near " (a INT)" (total length 27)
mysql> CREATE TABLE `select` (a INT);
Query OK, 0 rows affected (0.09 sec)

The BEGIN and END are keywords but not reserved words, so you do not need to quote them with backquotes:

mysql> CREATE TABLE `select` (BEGIN int, END int);
Query OK, 0 rows affected (0.09 sec)

Exception: A word that follows a period . qualifier does not need to be quoted with backquotes either:

mysql> CREATE TABLE test.select (BEGIN int, END int);
Query OK, 0 rows affected (0.08 sec)

The following table lists the keywords and reserved words in TiDB. The reserved words are labelled with ®.

ACTION ADD ® ADDDATE
ADMIN AFTER ALL ®
ALTER ® ALWAYS ANALYZE®
AND ® ANY AS ®
ASC ® ASCII AUTO_INCREMENT
AVG AVG_ROW_LENGTH BEGIN
BETWEEN ® BIGINT ® BINARY ®
BINLOG BIT BIT_XOR
BLOB ® BOOL BOOLEAN
BOTH ® BTREE BY ®
BYTE CASCADE ® CASE ®
CAST CHANGE ® CHAR ®
CHARACTER ® CHARSET CHECK ®
CHECKSUM COALESCE COLLATE ®
COLLATION COLUMN ® COLUMNS
COMMENT COMMIT COMMITTED
COMPACT COMPRESSED COMPRESSION
CONNECTION CONSISTENT CONSTRAINT ®
CONVERT ® COUNT CREATE ®
CROSS ® CURRENT_DATE ® CURRENT_TIME ®
CURRENT_TIMESTAMP ® CURRENT_USER ® CURTIME
DATA DATABASE ® DATABASES ®
DATE DATE_ADD DATE_SUB
DATETIME DAY DAY_HOUR ®
DAY_MICROSECOND ® DAY_MINUTE ® DAY_SECOND ®
DDL DEALLOCATE DEC
DECIMAL ® DEFAULT ® DELAY_KEY_WRITE
DELAYED ® DELETE ® DESC ®
DESCRIBE ® DISABLE DISTINCT ®
DISTINCTROW ® DIV ® DO
DOUBLE ® DROP ® DUAL ®
DUPLICATE DYNAMIC ELSE ®
ENABLE ENCLOSED END
ENGINE ENGINES ENUM
ESCAPE ESCAPED EVENTS
EXCLUSIVE EXECUTE EXISTS
EXPLAIN ® EXTRACT FALSE ®
FIELDS FIRST FIXED
FLOAT ® FLUSH FOR ®
FORCE ® FOREIGN ® FORMAT
FROM ® FULL FULLTEXT ®
FUNCTION GENERATED ® GET_FORMAT
GLOBAL GRANT ® GRANTS
GROUP ® GROUP_CONCAT HASH
HAVING ® HIGH_PRIORITY ® HOUR
HOUR_MICROSECOND ® HOUR_MINUTE ® HOUR_SECOND ®
IDENTIFIED IF ® IGNORE ®
IN ® INDEX ® INDEXES
INFILE ® INNER ® INSERT ®
INT ® INTEGER ® INTERVAL ®
INTO ® IS ® ISOLATION
JOBS JOIN ® JSON
KEY ® KEY_BLOCK_SIZE KEYS ®
KILL ® LEADING ® LEFT ®
LESS LEVEL LIKE ®
LIMIT ® LINES ® LOAD ®
LOCAL LOCALTIME ® LOCALTIMESTAMP ®
LOCK ® LONGBLOB ® LONGTEXT ®
LOW_PRIORITY ® MAX MAX_ROWS
MAXVALUE ® MEDIUMBLOB ® MEDIUMINT ®
MEDIUMTEXT ® MICROSECOND MIN
MIN_ROWS MINUTE MINUTE_MICROSECOND ®
MINUTE_SECOND ® MIN MIN_ROWS
MINUTE MINUTE_MICROSECOND MINUTE_SECOND
MOD ® MODE MODIRY
MONTH NAMES NATIONAL
NATURAL ® NO NO_WRITE_TO_BINLOG ®
NONE NOT ® NOW
NULL ® NUMERIC ® NVARCHAR ®
OFFSET ON ® ONLY
OPTION ® OR ® ORDER ®
OUTER ® PARTITION ® PARTITIONS
PASSWORD PLUGINS POSITION
PRECISION ® PREPARE PRIMARY ®
PRIVILEGES PROCEDURE ® PROCESS
PROCESSLIST QUARTER QUERY
QUICK RANGE ® READ ®
REAL ® REDUNDANT REFERENCES ®
REGEXP ® RENAME ® REPEAT ®
REPEATABLE REPLACE ® RESTRICT ®
REVERSE REVOKE ® RIGHT ®
RLIKE ® ROLLBACK ROW
ROW_COUNT ROW_FORMAT SCHEMA
SCHEMAS SECOND SECOND_MICROSECOND ®
SELECT ® SERIALIZABLE SESSION
SET ® SHARE SHARED
SHOW ® SIGNED SMALLINT ®
SNAPSHOT SOME SQL_CACHE
SQL_CALC_FOUND_ROWS ® SQL_NO_CACHE START
STARTING ® STATS STATS_BUCKETS
STATS_HISTOGRAMS STATS_META STATS_PERSISTENT
STATUS STORED ® SUBDATE
SUBSTR SUBSTRING SUM
SUPER TABLE ® TABLES
TERMINATED ® TEXT THAN
THEN ® TIDB TIDB_INLJ
TIDB_SMJ TIME TIMESTAMP
TIMESTAMPADD TIMESTAMPDIFF TINYBLOB ®
TINYINT ® TINYTEXT ® TO ®
TRAILING ® TRANSACTION TRIGGER ®
TRIGGERS TRIM TRUE ®
TRUNCATE UNCOMMITTED UNION ®
UNIQUE ® UNKNOWN UNLOCK ®
UNSIGNED ® UPDATE ® USE ®
USER USING ® UTC_DATE ®
UTC_TIME ® UTC_TIMESTAMP ® VALUE
VALUES ® VARBINARY ® VARCHAR ®
VARIABLES VIEW VIRTUAL ®
WARNINGS WEEK WHEN ®
WHERE ® WITH ® WRITE ®
XOR ® YEAR YEAR_MONTH ®
ZEROFILL ®
"Keywords and Reserved Words" was last updated Nov 23 2018: *: add v1.0 and v2.0 docs subdirectories (#760) (cbc4ffb)
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