MySQL 5.7中的關鍵字和保留字

yuntui發表於2016-11-03
MySql
最近在將資料從Oracle遷移到MySQL的過程中，遇到一些問題，其中就包括關鍵字。

MySQL和Oracle的關鍵字還是不盡相同的，在Oracle資料庫中，我們的資料表中定義了大量的code欄位用來表示主鍵，但是在MySQL中code是關鍵字，使用以前的處理方法就有些“水土不服”。

下面我們來了解一下MySQL中的關鍵字和保留字。

什麼是關鍵字和保留字

關鍵字是指在SQL中有意義的字。 某些關鍵字（例如SELECT，DELETE或BIGINT）是保留的，需要特殊處理才能用作表和列名稱等識別符號。 這一點對於內建函式的名稱也適用。

如何使用關鍵字和保留字

非保留關鍵字允許作為識別符號，不需要加引號。 如果您要適用保留字作為識別符號，就必須適用引號。

舉個例子，BEGIN和END是關鍵字，但不是保留字，因此它們用作識別符號不需要引號。 INTERVAL是保留關鍵字，必須加上引號才能用作識別符號。

點選(此處)摺疊或開啟

  1. mysql>
  2. mysql> use hoegh;
  3. Database changed
  4. mysql>
  5. mysql> CREATE TABLE interval (begin INT, end INT);
  6. ERROR 1064 (42000):
  7. mysql>
  8. mysql> CREATE TABLE `interval` (begin INT, end INT);
  9. Query OK, 0 rows affected (0.42 sec)

  11. mysql>
  12. mysql> show create table `interval`;
  13. +----------+---------------------------------------------------------
  14. | Table | Create Table
  15. +----------+---------------------------------------------------------
  16. | interval | CREATE TABLE `interval` (
  17.   `begin` int(11) DEFAULT NULL,
  18.   `end` int(11) DEFAULT NULL
  19. ) ENGINE=InnoDB DEFAULT CHARSET=latin1 |
  20. +----------+---------------------------------------------------------
  21. 1 row in set (0.00 sec)

  23. mysql>
我們看到，第一條語句中表名使用了保留字interval，執行失敗；
第二條語句對interval加了引號，執行成功。

在這裡需要注意的是，引號必須是反引號，而非單引號。否則會報錯，如下所示：

點選(此處)摺疊或開啟

  1. mysql>
  2. mysql> drop table `interval`;--使用反引號
  3. Query OK, 0 rows affected (0.11 sec)

  5. mysql>
  6. mysql> create table 'interval' (begin INT, end INT);--使用單引號，報錯
  7. ERROR 1064 (42000):

  9. mysql>

有一個例外

如果識別符號在限定名稱（資料庫名）的句點之後，即使是保留關鍵字也不需要引號。

我們以hoegh資料庫為例，如果表名寫為hoegh.interval就不需要對保留字interval加引號了。

點選(此處)摺疊或開啟

  1. mysql>
  2. mysql> create table hoegh.interval (begin INT, end INT);
  3. Query OK, 0 rows affected (0.19 sec)

  5. mysql>
  6. mysql> show create table hoegh.interval;
  7. +----------+---------------------------------------------------------
  8. | Table | Create Table
  9. +----------+---------------------------------------------------------
  10. | interval | CREATE TABLE `interval` (
  11.   `begin` int(11) DEFAULT NULL,
  12.   `end` int(11) DEFAULT NULL
  13. ) ENGINE=InnoDB DEFAULT CHARSET=latin1 |
  14. +----------+---------------------------------------------------------
  15. 1 row in set (0.00 sec)

  17. mysql>

關於使用內建函式名稱

允許內建函式的名稱可以作為識別符號，但最好謹慎使用。例如，COUNT作為列名稱是合法的。但是，預設情況下，在函式名和後面的（之間的函式呼叫中不允許有空格。這個限制使解析器能夠區分名稱是用於函式呼叫還是用在非函式上下文中。

附錄

在某些時候，您可能需要升級到更高版本，因此最好檢視一下未來的保留字。您可以在涵蓋更高版本的MySQL的手冊中找到這些。對於表中的大多數保留字，在標準SQL中禁止作為列或表的名稱（例如，GROUP）。其中一些保留字，是由於MySQL需要它們並使用一個yacc解析器。

以下列出三張表格：
第一個表格10.2顯示MySQL 5.7中的關鍵字和保留字。保留的關鍵字標記為（R）。此外，_FILENAME是保留的。
第二個表格10.3顯示MySQL 5.7相比5.6版本新增的保留字。
第三個表格10.4顯示MySQL 5.7相比5.6版本刪除的保留字。


Table 10.2 Keywords and Reserved Words in MySQL 5.7

ACCESSIBLE (R) ACCOUNT[a] ACTION
ADD (R) AFTER AGAINST
AGGREGATE ALGORITHM ALL (R)
ALTER (R) ALWAYS[b] ANALYSE
ANALYZE (R) AND (R) ANY
AS (R) ASC (R) ASCII
ASENSITIVE (R) AT AUTOEXTEND_SIZE
AUTO_INCREMENT AVG AVG_ROW_LENGTH
BACKUP BEFORE (R) BEGIN
BETWEEN (R) BIGINT (R) BINARY (R)
BINLOG BIT BLOB (R)
BLOCK BOOL BOOLEAN
BOTH (R) BTREE BY (R)
BYTE CACHE CALL (R)
CASCADE (R) CASCADED CASE (R)
CATALOG_NAME CHAIN CHANGE (R)
CHANGED CHANNEL[c] CHAR (R)
CHARACTER (R) CHARSET CHECK (R)
CHECKSUM CIPHER CLASS_ORIGIN
CLIENT CLOSE COALESCE
CODE COLLATE (R) COLLATION
COLUMN (R) COLUMNS COLUMN_FORMAT
COLUMN_NAME COMMENT COMMIT
COMMITTED COMPACT COMPLETION
COMPRESSED COMPRESSION[d] CONCURRENT
CONDITION (R) CONNECTION CONSISTENT
CONSTRAINT (R) CONSTRAINT_CATALOG CONSTRAINT_NAME
CONSTRAINT_SCHEMA CONTAINS CONTEXT
CONTINUE (R) CONVERT (R) CPU
CREATE (R) CROSS (R) CUBE
CURRENT CURRENT_DATE (R) CURRENT_TIME (R)
CURRENT_TIMESTAMP (R) CURRENT_USER (R) CURSOR (R)
CURSOR_NAME DATA DATABASE (R)
DATABASES (R) DATAFILE DATE
DATETIME DAY DAY_HOUR (R)
DAY_MICROSECOND (R) DAY_MINUTE (R) DAY_SECOND (R)
DEALLOCATE DEC (R) DECIMAL (R)
DECLARE (R) DEFAULT (R) DEFAULT_AUTH
DEFINER DELAYED (R) DELAY_KEY_WRITE
DELETE (R) DESC (R) DESCRIBE (R)
DES_KEY_FILE DETERMINISTIC (R) DIAGNOSTICS
DIRECTORY DISABLE DISCARD
DISK DISTINCT (R) DISTINCTROW (R)
DIV (R) DO DOUBLE (R)
DROP (R) DUAL (R) DUMPFILE
DUPLICATE DYNAMIC EACH (R)
ELSE (R) ELSEIF (R) ENABLE
ENCLOSED (R) ENCRYPTION[e] END
ENDS ENGINE ENGINES
ENUM ERROR ERRORS
ESCAPE ESCAPED (R) EVENT
EVENTS EVERY EXCHANGE
EXECUTE EXISTS (R) EXIT (R)
EXPANSION EXPIRE EXPLAIN (R)
EXPORT EXTENDED EXTENT_SIZE
FALSE (R) FAST FAULTS
FETCH (R) FIELDS FILE
FILE_BLOCK_SIZE[f] FILTER[g] FIRST
FIXED FLOAT (R) FLOAT4 (R)
FLOAT8 (R) FLUSH FOLLOWS[h]
FOR (R) FORCE (R) FOREIGN (R)
FORMAT FOUND FROM (R)
FULL FULLTEXT (R) FUNCTION
GENERAL GENERATED[i] (R) GEOMETRY
GEOMETRYCOLLECTION GET (R) GET_FORMAT
GLOBAL GRANT (R) GRANTS
GROUP (R) GROUP_REPLICATION[j] HANDLER
HASH HAVING (R) HELP
HIGH_PRIORITY (R) HOST HOSTS
HOUR HOUR_MICROSECOND (R) HOUR_MINUTE (R)
HOUR_SECOND (R) IDENTIFIED IF (R)
IGNORE (R) IGNORE_SERVER_IDS IMPORT
IN (R) INDEX (R) INDEXES
INFILE (R) INITIAL_SIZE INNER (R)
INOUT (R) INSENSITIVE (R) INSERT (R)
INSERT_METHOD INSTALL INSTANCE[k]
INT (R) INT1 (R) INT2 (R)
INT3 (R) INT4 (R) INT8 (R)
INTEGER (R) INTERVAL (R) INTO (R)
INVOKER IO IO_AFTER_GTIDS (R)
IO_BEFORE_GTIDS (R) IO_THREAD IPC
IS (R) ISOLATION ISSUER
ITERATE (R) JOIN (R) JSON[l]
KEY (R) KEYS (R) KEY_BLOCK_SIZE
KILL (R) LANGUAGE LAST
LEADING (R) LEAVE (R) LEAVES
LEFT (R) LESS LEVEL
LIKE (R) LIMIT (R) LINEAR (R)
LINES (R) LINESTRING LIST
LOAD (R) LOCAL LOCALTIME (R)
LOCALTIMESTAMP (R) LOCK (R) LOCKS
LOGFILE LOGS LONG (R)
LONGBLOB (R) LONGTEXT (R) LOOP (R)
LOW_PRIORITY (R) MASTER MASTER_AUTO_POSITION
MASTER_BIND (R) MASTER_CONNECT_RETRY MASTER_DELAY
MASTER_HEARTBEAT_PERIOD MASTER_HOST MASTER_LOG_FILE
MASTER_LOG_POS MASTER_PASSWORD MASTER_PORT
MASTER_RETRY_COUNT MASTER_SERVER_ID MASTER_SSL
MASTER_SSL_CA MASTER_SSL_CAPATH MASTER_SSL_CERT
MASTER_SSL_CIPHER MASTER_SSL_CRL MASTER_SSL_CRLPATH
MASTER_SSL_KEY MASTER_SSL_VERIFY_SERVER_CERT(R) MASTER_TLS_VERSION[m]
MASTER_USER MATCH (R) MAXVALUE (R)
MAX_CONNECTIONS_PER_HOUR MAX_QUERIES_PER_HOUR MAX_ROWS
MAX_SIZE MAX_STATEMENT_TIME[n] MAX_UPDATES_PER_HOUR
MAX_USER_CONNECTIONS MEDIUM MEDIUMBLOB (R)
MEDIUMINT (R) MEDIUMTEXT (R) MEMORY
MERGE MESSAGE_TEXT MICROSECOND
MIDDLEINT (R) MIGRATE MINUTE
MINUTE_MICROSECOND (R) MINUTE_SECOND (R) MIN_ROWS
MOD (R) MODE MODIFIES (R)
MODIFY MONTH MULTILINESTRING
MULTIPOINT MULTIPOLYGON MUTEX
MYSQL_ERRNO NAME NAMES
NATIONAL NATURAL (R) NCHAR
NDB NDBCLUSTER NEVER[o]
NEW NEXT NO
NODEGROUP NONBLOCKING[p] NONE
NOT (R) NO_WAIT NO_WRITE_TO_BINLOG (R)
NULL (R) NUMBER NUMERIC (R)
NVARCHAR OFFSET OLD_PASSWORD[q]
ON (R) ONE ONLY
OPEN OPTIMIZE (R) OPTIMIZER_COSTS[r] (R)
OPTION (R) OPTIONALLY (R) OPTIONS
OR (R) ORDER (R) OUT (R)
OUTER (R) OUTFILE (R) OWNER
PACK_KEYS PAGE PARSER
PARSE_GCOL_EXPR[s] PARTIAL PARTITION (R)
PARTITIONING PARTITIONS PASSWORD
PHASE PLUGIN PLUGINS
PLUGIN_DIR POINT POLYGON
PORT PRECEDES[t] PRECISION (R)
PREPARE PRESERVE PREV
PRIMARY (R) PRIVILEGES PROCEDURE (R)
PROCESSLIST PROFILE PROFILES
PROXY PURGE (R) QUARTER
QUERY QUICK RANGE (R)
READ (R) READS (R) READ_ONLY
READ_WRITE (R) REAL (R) REBUILD
RECOVER REDOFILE REDO_BUFFER_SIZE
REDUNDANT REFERENCES (R) REGEXP (R)
RELAY RELAYLOG RELAY_LOG_FILE
RELAY_LOG_POS RELAY_THREAD RELEASE (R)
RELOAD REMOVE RENAME (R)
REORGANIZE REPAIR REPEAT (R)
REPEATABLE REPLACE (R) REPLICATE_DO_DB[u]
REPLICATE_DO_TABLE[v] REPLICATE_IGNORE_DB[w] REPLICATE_IGNORE_TABLE[x]
REPLICATE_REWRITE_DB[y] REPLICATE_WILD_DO_TABLE[z] REPLICATE_WILD_IGNORE_TABLE[aa]
REPLICATION REQUIRE (R) RESET
RESIGNAL (R) RESTORE RESTRICT (R)
RESUME RETURN (R) RETURNED_SQLSTATE
RETURNS REVERSE REVOKE (R)
RIGHT (R) RLIKE (R) ROLLBACK
ROLLUP ROTATE[ab] ROUTINE
ROW ROWS ROW_COUNT
ROW_FORMAT RTREE SAVEPOINT
SCHEDULE SCHEMA (R) SCHEMAS (R)
SCHEMA_NAME SECOND SECOND_MICROSECOND (R)
SECURITY SELECT (R) SENSITIVE (R)
SEPARATOR (R) SERIAL SERIALIZABLE
SERVER SESSION SET (R)
SHARE SHOW (R) SHUTDOWN
SIGNAL (R) SIGNED SIMPLE
SLAVE SLOW SMALLINT (R)
SNAPSHOT SOCKET SOME
SONAME SOUNDS SOURCE
SPATIAL (R) SPECIFIC (R) SQL (R)
SQLEXCEPTION (R) SQLSTATE (R) SQLWARNING (R)
SQL_AFTER_GTIDS SQL_AFTER_MTS_GAPS SQL_BEFORE_GTIDS
SQL_BIG_RESULT (R) SQL_BUFFER_RESULT SQL_CACHE
SQL_CALC_FOUND_ROWS (R) SQL_NO_CACHE SQL_SMALL_RESULT (R)
SQL_THREAD SQL_TSI_DAY SQL_TSI_HOUR
SQL_TSI_MINUTE SQL_TSI_MONTH SQL_TSI_QUARTER
SQL_TSI_SECOND SQL_TSI_WEEK SQL_TSI_YEAR
SSL (R) STACKED START
STARTING (R) STARTS STATS_AUTO_RECALC
STATS_PERSISTENT STATS_SAMPLE_PAGES STATUS
STOP STORAGE STORED[ac] (R)
STRAIGHT_JOIN (R) STRING SUBCLASS_ORIGIN
SUBJECT SUBPARTITION SUBPARTITIONS
SUPER SUSPEND SWAPS
SWITCHES TABLE (R) TABLES
TABLESPACE TABLE_CHECKSUM TABLE_NAME
TEMPORARY TEMPTABLE TERMINATED (R)
TEXT THAN THEN (R)
TIME TIMESTAMP TIMESTAMPADD
TIMESTAMPDIFF TINYBLOB (R) TINYINT (R)
TINYTEXT (R) TO (R) TRAILING (R)
TRANSACTION TRIGGER (R) TRIGGERS
TRUE (R) TRUNCATE TYPE
TYPES UNCOMMITTED UNDEFINED
UNDO (R) UNDOFILE UNDO_BUFFER_SIZE
UNICODE UNINSTALL UNION (R)
UNIQUE (R) UNKNOWN UNLOCK (R)
UNSIGNED (R) UNTIL UPDATE (R)
UPGRADE USAGE (R) USE (R)
USER USER_RESOURCES USE_FRM
USING (R) UTC_DATE (R) UTC_TIME (R)
UTC_TIMESTAMP (R) VALIDATION[ad] VALUE
VALUES (R) VARBINARY (R) VARCHAR (R)
VARCHARACTER (R) VARIABLES VARYING (R)
VIEW VIRTUAL[ae] (R) WAIT
WARNINGS WEEK WEIGHT_STRING
WHEN (R) WHERE (R) WHILE (R)
WITH (R) WITHOUT[af] WORK
WRAPPER WRITE (R) X509
XA XID[ag] XML
XOR (R) YEAR YEAR_MONTH (R)
ZEROFILL (R)    

[a] ACCOUNT: added in 5.7.6 (nonreserved)

[b] ALWAYS: added in 5.7.6 (nonreserved)

[c] CHANNEL: added in 5.7.6 (nonreserved)

[d] COMPRESSION: added in 5.7.8 (nonreserved)

[e] ENCRYPTION: added in 5.7.11 (nonreserved)

[f] FILE_BLOCK_SIZE: added in 5.7.6 (nonreserved)

[g] FILTER: added in 5.7.3 (nonreserved)

[h] FOLLOWS: added in 5.7.2 (nonreserved)

[i] GENERATED: added in 5.7.6 (reserved)

[j] GROUP_REPLICATION: added in 5.7.6 (nonreserved)

[k] INSTANCE: added in 5.7.11 (nonreserved)

[l] JSON: added in 5.7.8 (nonreserved)

[m] MASTER_TLS_VERSION: added in 5.7.10 (nonreserved)

[n] MAX_STATEMENT_TIME: added in 5.7.4 (nonreserved); removed in 5.7.8

[o] NEVER: added in 5.7.4 (nonreserved)

[p] NONBLOCKING: removed in 5.7.6

[q] OLD_PASSWORD: removed in 5.7.5

[r] OPTIMIZER_COSTS: added in 5.7.5 (reserved)

[s] PARSE_GCOL_EXPR: added in 5.7.6 (reserved); became nonreserved in 5.7.8

[t] PRECEDES: added in 5.7.2 (nonreserved)

[u] REPLICATE_DO_DB: added in 5.7.3 (nonreserved)

[v] REPLICATE_DO_TABLE: added in 5.7.3 (nonreserved)

[w] REPLICATE_IGNORE_DB: added in 5.7.3 (nonreserved)

[x] REPLICATE_IGNORE_TABLE: added in 5.7.3 (nonreserved)

[y] REPLICATE_REWRITE_DB: added in 5.7.3 (nonreserved)

[z] REPLICATE_WILD_DO_TABLE: added in 5.7.3 (nonreserved)

[aa] REPLICATE_WILD_IGNORE_TABLE: added in 5.7.3 (nonreserved)

[ab] ROTATE: added in 5.7.11 (nonreserved)

[ac] STORED: added in 5.7.6 (reserved)

[ad] VALIDATION: added in 5.7.5 (nonreserved)

[ae] VIRTUAL: added in 5.7.6 (reserved)

[af] WITHOUT: added in 5.7.5 (nonreserved)

[ag] XID: added in 5.7.5 (nonreserved)


Table 10.3 Keywords and Reserved Words Added in MySQL 5.7 Compared to MySQL 5.6

ACCOUNT ALWAYS CHANNEL
COMPRESSION ENCRYPTION FILE_BLOCK_SIZE
FILTER FOLLOWS GENERATED (R)
GROUP_REPLICATION INSTANCE JSON
MASTER_TLS_VERSION NEVER OPTIMIZER_COSTS (R)
PARSE_GCOL_EXPR PRECEDES REPLICATE_DO_DB
REPLICATE_DO_TABLE REPLICATE_IGNORE_DB REPLICATE_IGNORE_TABLE
REPLICATE_REWRITE_DB REPLICATE_WILD_DO_TABLE REPLICATE_WILD_IGNORE_TABLE
ROTATE STACKED STORED (R)
VALIDATION VIRTUAL (R) WITHOUT
XID    

Table 10.4 Keywords and Reserved Words Removed in MySQL 5.7 Compared to MySQL 5.6

OLD_PASSWORD    



~~~~~~~ the end~~~~~~~~~
hoegh
2016.11.02


來自 “ ITPUB部落格 ” ，連結：http://blog.itpub.net/30633755/viewspace-2127708/，如需轉載，請註明出處，否則將追究法律責任。

相關文章