# 关键字 本章介绍 MatrixOne 的关键字，在 MatrixOne 中对保留关键字和非保留关键字进行了分类，你在使用 SQL 语句时，可以查阅保留关键字和非保留关键字。 **关键字**是 SQL 语句中具有特殊含义的单词，例如 `SELECT`，`UPDATE`，`DELETE` 等等。 - **保留关键字**：关键字中需要经过特殊处理才能作为标识符的字，被称为保留关键字。 将保留关键字作为标识符使用时，必须使用反引号包裹，否则将产生报错： ```text \\未将保留关键字 select 使用反引号包裹，产生报错 mysql> CREATE TABLE select (a INT); ERROR 1064 (HY000): SQL parser error: You have an error in your SQL syntax; check the manual that corresponds to your MatrixOne server version for the right syntax to use. syntax error at line 1 column 19 near " select (a INT)"; \\正确将保留关键字 select 使用反引号包裹 mysql> CREATE TABLE `select` (a INT); Query OK, 0 rows affected (0.02 sec) ``` - **非保留关键字**：关键字中可以直接作为标识符，被称为非保留关键字。 将非保留关键字作为标识符使用时，可以直接使用，无需使用反引号包裹。 ```text \\ACCOUNT 为非保留关键字，可以无需使用反引号包裹 mysql> CREATE TABLE `select` (ACCOUNT int); Query OK, 0 rows affected (0.01 sec) ``` :::{note} 与 MySQL 不同，在 MatrixOne 中，如果使用了限定符*.*，保留关键字如果不使用反引号包裹也会产生报错，建议在创建表和数据库时，避免使用保留关键字： ::: ```text mysql> CREATE TABLE test.select (ACCOUNT int); ERROR 1064 (HY000): SQL parser error: You have an error in your SQL syntax; check the manual that corresponds to your MatrixOne server version for the right syntax to use. syntax error at line 1 column 24 near "select (ACCOUNT int)"; ``` 下面的列表显示了 Matrixone 中的保留关键字和非保留关键字，其中，在 MySQL 中不为关键字的用 **(M)** 标记。 ## 保留关键字 ### A - ADD - ALL - ALTER - ANALYZE - AND - AS - ASC ### B - BEGIN - BETWEEN - BINARY - BOTH - BY ### C - CALL - CASE - CHANGE - CHAR - CHARACTER - CHECK - COLLATE - COLUMN - CONFIG **(M)** - CONSTRAINT - CONVERT - CREATE - CROSS - CURRENT_DATE - CURRENT_ROLE **(M)** - CURRENT_TIME - CURRENT_TIMESTAMP - CURRENT_USER ### D - DATABASE - DATABASES - DAY_HOUR - DAY_MICROSECOND - DAY_MINUTE - DAY_SECOND - DECLARE - DEFAULT - DELAYED - DELETE - DENSE_RANK - DESC - DESCRIBE - DISTINCT - DIV - DROP ### E - ELSE - ELSEIF - ENCLOSED - END - ESCAPE - ESCAPED - EXCEPT - EXISTS - EXPLAIN ### F - FALSE **(M)** - FOR - FORCE - FOREIGN - FROM - FULLTEXT - FUNCTION ### G - GROUP - GROUPS ### H - HAVING - HIGH_PRIORITY - HOUR_MICROSECOND - HOUR_MINUTE - HOUR_SECOND ### I - IF - IGNORE - ILIKE **(M)** - IN - INDEX - INFILE - INNER - INOUT - INSERT - INT1 - INT2 - INT3 - INT4 - INT8 - INTERSECT - INTERVAL - INTO - IS - ITERATE ### J - JOIN ### K - KEY - KILL ### L - LEADING - LEAVE - LEFT - LIKE - LIMIT - LINES - LOAD - LOCALTIME - LOCALTIMESTAMP - LOCK - LOOP - LOW_PRIORITY ### M - MATCH - MAXVALUE - MINUS **(M)** - MINUTE_MICROSECOND - MINUTE_SECOND - MOD ### N - NATURAL - NOT - NULL ### O - ON - OPTIONALLY - OR - ORDER - OUT - OUTER - OUTFILE - OVER ### P - PARTITION - PRIMARY ### Q - QUICK ### R - RANK - RECURSIVE - REFERENCES - REGEXP - RENAME - REPEAT - REPLACE - REQUIRE - RIGHT - RLIKE - ROW - ROW_NUMBER - ROWS ### S - SCHEMA - SCHEMAS - SECOND_MICROSECOND - SELECT - SEPARATOR - SET - SHOW - SQL_BIG_RESULT - SQL_BUFFER_RESULT - SQL_SMALL_RESULT - SSL - STARTING - STRAIGHT_JOIN ### T - TABLE - TEMPORARY - TERMINATED - THEN - TO - TRAILING - TRUE **(M)** ### U - UNION - UNIQUE - UNTIL - UPDATE - USAGE - USE - USING - UTC_DATE - UTC_TIME - UTC_TIMESTAMP ### V - VALUES ### W - WHEN - WHERE - WHILE - WITH ### X - XOR ### Y - YEAR_MONTH ### _ - _BINARY **(M)** ## 非保留关键字 ### A - ACCOUNT - ACCOUNTS **(M)** - ACTION - ADMIN_NAME **(M)** - AFTER - AGAINST - ALGORITHM - ANY - ASCII - ATTRIBUTE - AUTO_INCREMENT - AUTO_RANDOM **(M)** - AUTOEXTEND_SIZE - AVG_ROW_LENGTH ### B - BACKEND **(M)** - BACKUP - BIGINT - BINDINGS **(M)** - BIT - BLOB - BOOL - BOOLEAN - BSI **(M)** - BTREE ### C - CANCEL **(M)** - CASCADE - CASCADED - CHAIN - CHARSET - CHECKSUM - CIPHER - CLIENT - CLUSTER **(M)** - COALESCE - COLLATION - COLUMN_FORMAT - COLUMN_NUMBER **(M)** - COLUMNS - COMMENT - COMMIT - COMMITTED - COMPACT - COMPRESSED - COMPRESSION - CONNECT **(M)** - CONNECTION - CONNECTOR **(M)** - CONNECTORS **(M)** - CONSISTENT - COPY **(M)** - CREDENTIALS **(M)** - CURRENT - CYCLE **(M)** ### D - DAEMON **(M)** - DATA - DATE - DATETIME - DAY - DEALLOCATE - DECIMAL - DEFINER - DELAY_KEY_WRITE - DIRECTORY - DISABLE - DISCARD - DISK - DO - DOUBLE - DRAINER **(M)** - DUPLICATE - DYNAMIC ### E - ENABLE - ENCRYPTION - ENFORCED - ENGINE - ENGINE_ATTRIBUTE - ENGINES - ENUM - ERRORS - EVENT - EVENTS - EXCLUSIVE **(M)** - EXECUTE - EXPANSION **(M)** - EXPIRE - EXTENDED - EXTENSION - EXTERNAL **(M)** ### F - FAILED_LOGIN_ATTEMPTS - FIELDS - FILE - FILESYSTEM **(M)** - FILL **(M)** - FIRST - FIXED - FLOAT - FOLLOWING - FORCE_QUOTE **(M)** - FORMAT - FULL ### G - GEOMETRY - GEOMETRYCOLLECTION - GLOBAL - GRANT - GRANTS ### H - HANDLER - HASH - HEADER **(M)** - HISTORY - HOUR ### I - IDENTIFIED - IMPORT - INCREMENT **(M)** - INDEXES - INLINE **(M)** - INPLACE **(M)** - INSERT_METHOD - INSTANT **(M)** - INT - INTEGER - INVISIBLE - INVOKER - ISOLATION - ISSUER - IVFFLAT **(M)** ### J - JSON - JSONTYPE **(M)** ### K - KEY_BLOCK_SIZE - KEYS ### L - LANGUAGE - LAST - LESS - LEVEL - LINEAR - LINESTRING - LIST - LISTS **(M)** - LOCAL - LOCKS - LONGBLOB - LONGTEXT - LOW_CARDINALITY **(M)** ### M - MANAGE **(M)** - MASTER - MAX_CONNECTIONS_PER_HOUR - MAX_FILE_SIZE **(M)** - MAX_QUERIES_PER_HOUR - MAX_ROWS - MAX_UPDATE_PER_HOUR **(M)** - MAX_USER_CONNECTIONS - MEDIAN **(M)** - MEDIUMBLOB - MEDIUMINT - MEDIUMTEXT - MEMORY - MERGE - MICROSECOND - MIN_ROWS - MINUTE - MINVALUE **(M)** - MODE - MODIFY - MODUMP **(M)** - MONTH - MULTILINESTRING - MULTIPOINT - MULTIPOLYGON - MYSQL_COMPATIBILITY_MODE **(M)** ### N - NAMES - NCHAR - NEVER - NEXT - NO - NODE **(M)** - NONE - NULLS - NUMERIC ### O - OFFSET - ONLY - OP_TYPE **(M)** - OPEN - OPTIMIZE - OPTION - OPTIONAL - OWNERSHIP **(M)** ### P - PACK_KEYS - PARALLEL **(M)** - PARALLELISM **(M)** - PARSER - PARTIAL - PARTITIONS - PASSWORD - PASSWORD_LOCK_TIME - PAUSE **(M)** - PERCENT **(M)** - PERSIST - PLUGINS - POINT - POLYGON - PRECEDING - PREPARE - PREV - PRIVILEGES - PROCEDURE - PROCESSLIST - PROFILES - PROPERTIES **(M)** - PROXY - PUBLICATION **(M)** - PUBLICATIONS **(M)** - PUMP **(M)** ### Q - QUARTER - QUERY - QUERY_RESULT **(M)** ### R - RANDOM - RANGE - READ - REAL - REDUNDANT - REFERENCE - RELEASE - RELOAD - REORGANIZE - REPAIR - REPEATABLE - REPLICATION - RESET - RESTRICT - RESTRICTED **(M)** - RESUME - RETURNS - REUSE - REVERSE - REVOKE - ROLE - ROLES **(M)** - ROLLBACK - ROUTINE - ROW_COUNT - ROW_FORMAT - RTREE ### S - S3OPTION **(M)** - SAMPLE **(M)** - SAN **(M)** - SECOND - SECONDARY - SECONDARY_ENGINE_ATTRIBUTE - SECURITY - SEQUENCE **(M)** - SEQUENCES **(M)** - SERIALIZABLE - SERVERS **(M)** - SESSION - SHARE - SHARED **(M)** - SHUTDOWN - SIGNED - SIMPLE - SLAVE - SLIDING **(M)** - SMALLINT - SNAPSHOT - SOME - SOURCE - SPATIAL - SQL - SQL_CACHE - SQL_NO_CACHE - SQL_TSI_DAY - SQL_TSI_HOUR - SQL_TSI_MINUTE - SQL_TSI_MONTH - SQL_TSI_QUARTER - SQL_TSI_SECOND - SQL_TSI_WEEK - SQL_TSI_YEAR - STAGE **(M)** - STAGEOPTION **(M)** - STAGES **(M)** - START - STATS_AUTO_RECALC - STATS_PERSISTENT - STATS_SAMPLE_PAGES - STATUS - STORAGE - STREAM - SUBJECT - SUBPARTITION - SUBPARTITIONS - SUBSCRIPTIONS **(M)** - SUPER - SUSPEND ### T - TABLE_NUMBER **(M)** - TABLE_SIZE **(M)** - TABLE_VALUES **(M)** - TABLES - TABLESPACE - TASK **(M)** - TEMPTABLE - TEXT - THAN - TIME - TIMESTAMP - TINYBLOB - TINYINT - TINYTEXT - TRANSACTION - TRIGGER - TRIGGERS - TRUNCATE - TYPE ### U - UNBOUNDED - UNCOMMITTED - UNDEFINED - UNKNOWN - UNLOCK - UNSIGNED - URL - USER - UUID **(M)** ### V - VALIDATION - VALUE - VARBINARY - VARCHAR - VARIABLES - VECF32 **(M)** - VECF64 **(M)** - VERBOSE **(M)** - VIEW - VISIBLE ### W - WARNINGS - WEEK - WITHOUT - WORK - WRITE ### X - X509 ### Y - YEAR ### Z - ZEROFILL - ZONEMAP **(M)**