默认情况下，字符串可以用 " 以及 ' 括起来。如果 ANSI_QUOTES 启用 SQL 模式，字符串只能用 ' 括起来，服务器将 " 括起来的字符串解释为标识符。By default, strings can be enclosed by " as well as '. If the ANSI_QUOTES SQL mode is enabled, strings can be enclosed only by ' and the server interprets strings enclosed by " as identifiers.

\ 是字符串中的转义字符。\ is the escape character in strings.

在 SQL 语句中，您可以使用 db_name.tbl_name 语法访问不同数据库中的表。某些 SQL 服务器提供相同的功能，但称之为User space。 MySQL Server 不支持诸如以下语句中使用的表空间：CREATE TABLE ralph.my_table ... IN my_tablespace。In SQL statements, you can access tables from different databases with the db_name.tbl_name syntax. Some SQL servers provide the same functionality but call this User space. MySQL Server doesn't support tablespaces such as used in statements like this: CREATE TABLE ralph.my_table ... IN my_tablespace.

ANALYZE TABLE, CHECK TABLE、OPTIMIZE TABLE 和 REPAIR TABLE 语句。The ANALYZE TABLE, CHECK TABLE, OPTIMIZE TABLE, and REPAIR TABLE statements.

CREATE DATABASE、DROP DATABASE 和 ALTER DATABASE 语句。请参阅第 15.1.12 节“CREATE DATABASE 语句”、第 15.1.24 节“DROP DATABASE 语句”和第 15.1.2 节“ALTER DATABASE 语句”。The CREATE DATABASE, DROP DATABASE, and ALTER DATABASE statements. See Section 15.1.12, “CREATE DATABASE Statement”, Section 15.1.24, “DROP DATABASE Statement”, and Section 15.1.2, “ALTER DATABASE Statement”.

DO 语句。The DO statement.

EXPLAIN SELECT 获取查询优化器如何处理表的说明。EXPLAIN SELECT to obtain a description of how tables are processed by the query optimizer.

FLUSH 和 RESET 语句。The FLUSH and RESET statements.

SET 语句。请参阅第 15.7.6.1 节“SET 变量赋值语法”。The SET statement. See Section 15.7.6.1, “SET Syntax for Variable Assignment”.

该SHOW语句。参见第 15.7.7 节，“SHOW 语句”。由许多 MySQL 特定的SHOW可以通过使用更标准的方式获得语句SELECT来查询INFORMATION_SCHEMA。参见第 28 章，INFORMATION_SCHEMA 表.The SHOW statement. See Section 15.7.7, “SHOW Statements”. The information produced by many of the MySQL-specific SHOW statements can be obtained in more standard fashion by using SELECT to query INFORMATION_SCHEMA. See Chapter 28, INFORMATION_SCHEMA Tables.

LOAD DATA。在许多情况下，此语法与 Oracle LOAD DATA 兼容。请参阅第 15.2.9 节“LOAD DATA 语句”。 Use of LOAD DATA. In many cases, this syntax is compatible with Oracle LOAD DATA. See Section 15.2.9, “LOAD DATA Statement”.

使用 RENAME TABLE。请参阅第 15.1.36 节“RENAME TABLE 语句”。Use of RENAME TABLE. See Section 15.1.36, “RENAME TABLE Statement”.

使用 REPLACE 代替 DELETE 加上 INSERT。请参阅第 15.2.12 节“REPLACE 语句”。Use of REPLACE instead of DELETE plus INSERT. See Section 15.2.12, “REPLACE Statement”.

使用 CHANGE col_name、DROP col_name 或 DROP INDEX、IGNORE 或 RENAME。在 ALTER TABLE 语句中使用多个 ADD、ALTER、DROP 或 CHANGE 子句。请参阅第 15.1.9 节“ALTER TABLE 语句”。Use of CHANGE col_name, DROP col_name, or DROP INDEX, IGNORE or RENAME in ALTER TABLE statements. Use of multiple ADD, ALTER, DROP, or CHANGE clauses in an ALTER TABLE statement. See Section 15.1.9, “ALTER TABLE Statement”.

Use of index names, indexes on a prefix of a column, and use of INDEX或者KEY在CREATE TABLE statements. See Section 15.1.20, “CREATE TABLE Statement”.Use of index names, indexes on a prefix of a column, and use of INDEX or KEY in CREATE TABLE statements. See Section 15.1.20, “CREATE TABLE Statement”.

将 TEMPORARY 或 IF NOT EXISTS 与 CREATE TABLE。Use of TEMPORARY or IF NOT EXISTS with CREATE TABLE.

将 IF EXISTS 与 DROP TABLE 和 DROP DATABASE。Use of IF EXISTS with DROP TABLE and DROP DATABASE.

使用单个 DROP TABLE 语句删除多个表的功能。The capability of dropping multiple tables with a single DROP TABLE statement.

ORDER BY 和 LIMIT 子句。The ORDER BY and LIMIT clauses of the UPDATE and DELETE statements.

INSERT INTO tbl_name SET col_name = ... 语法。INSERT INTO tbl_name SET col_name = ... syntax.

该DELAYED子句的INSERT以及REPLACE语句。The DELAYED clause of the INSERT and REPLACE statements.

该LOW_PRIORITY子句的INSERT, REPLACE, DELETE，以及UPDATE语句。The LOW_PRIORITY clause of the INSERT, REPLACE, DELETE, and UPDATE statements.

在SELECT语句中使用INTO OUTFILE或INTO DUMPFILE。请参阅第 15.2.13 节“SELECT 语句”。Use of INTO OUTFILE or INTO DUMPFILE in SELECT statements. See Section 15.2.13, “SELECT Statement”.

Options such as STRAIGHT_JOIN或者SQL_SMALL_RESULT在SELECT语句。Options such as STRAIGHT_JOIN or SQL_SMALL_RESULT in SELECT statements.

您无需在 GROUP BY 子句中命名所有选定的列。这为一些非常具体但非常正常的查询提供了更好的性能。请参阅第 14.19 节“聚合函数”。You don't need to name all selected columns in the GROUP BY clause. This gives better performance for some very specific, but quite normal queries. See Section 14.19, “Aggregate Functions”.

您可以使用 ASC 指定 DESC 和 GROUP BY，而不仅仅是使用 ORDER BY。You can specify ASC and DESC with GROUP BY, not just with ORDER BY.

能够使用:= 赋值运算符在语句中设置变量。请参阅第 11.4 节“用户定义的变量”。The ability to set variables in a statement with the := assignment operator. See Section 11.4, “User-Defined Variables”.

MEDIUMINT、SET 和 ENUM 数据类型，以及各种 BLOB 和 TEXT 数据类型。The MEDIUMINT, SET, and ENUM data types, and the various BLOB and TEXT data types.

AUTO_INCREMENT、BINARY、NULL、UNSIGNED 和 ZEROFILL 数据类型属性。The AUTO_INCREMENT, BINARY, NULL, UNSIGNED, and ZEROFILL data type attributes.

为了方便从其他 SQL 环境迁移的用户，MySQL Server 支持许多函数的别名。例如，所有字符串函数都支持标准 SQL 语法和 ODBC 语法。To make it easier for users who migrate from other SQL environments, MySQL Server supports aliases for many functions. For example, all string functions support both standard SQL syntax and ODBC syntax.

MySQL Server 将 || 和 && 运算符理解为逻辑 OR 和 AND，就像在 C 编程语言中一样。在 MySQL Server 中，|| 和 OR 是同义词，&& 和AND。由于这种良好的语法，MySQL Server 不支持用于字符串连接的标准 SQL || 运算符；使用 CONCAT() 代替。由于 CONCAT() 可以接受任意数量的参数，因此可以轻松地将 || 运算符的使用转换为 MySQL Server。MySQL Server understands the || and && operators to mean logical OR and AND, as in the C programming language. In MySQL Server, || and OR are synonyms, as are && and AND. Because of this nice syntax, MySQL Server doesn't support the standard SQL || operator for string concatenation; use CONCAT() instead. Because CONCAT() takes any number of arguments, it is easy to convert use of the || operator to MySQL Server.

COUNT(DISTINCT value_list)，其中 value_list 包含多个元素。Use of COUNT(DISTINCT value_list) where value_list has more than one element.

字符串比较默认是不区分大小写的，排序顺序由当前字符集的校对规则决定，默认情况下是utf8mb4。要执行区分大小写的比较，应该在列声明中使用BINARY属性或使用BINARY类型转换，比较将使用底层字符代码值而非字典顺序进行。String comparisons are case-insensitive by default, with sort ordering determined by the collation of the current character set, which is utf8mb4 by default. To perform case-sensitive comparisons instead, you should declare your columns with the BINARY attribute or use the BINARY cast, which causes comparisons to be done using the underlying character code values rather than a lexical ordering.

% 运算符是 MOD() 的同义词。也就是说， N % M 相当于 MOD(N,M)。 % 支持 C 程序员并与 PostgreSQL 兼容。 The % operator is a synonym for MOD(). That is, N % M is equivalent to MOD(N,M). % is supported for C programmers and for compatibility with PostgreSQL.

=、<>、<=、<、>=、>、<<、>>、<=>、AND、OR 或 LIKE 运算符可以用在 SELECT 语句中输出列列表（FROM 左侧）的表达式中。例如：The =, <>, <=, <, >=, >, <<, >>, <=>, AND, OR, or LIKE operators may be used in expressions in the output column list (to the left of the FROM) in SELECT statements. For example:

mysql> SELECT col1=1 AND col2=2 FROM my_table;

LAST_INSERT_ID() 函数返回最新的AUTO_INCREMENT 值。请参阅第 14.15 节“信息函数”。The LAST_INSERT_ID() function returns the most recent AUTO_INCREMENT value. See Section 14.15, “Information Functions”.

LIKE 允许对数值进行操作。LIKE is permitted on numeric values.

REGEXP 和 NOT REGEXP 扩展正则表达式运算符。The REGEXP and NOT REGEXP extended regular expression operators.

CONCAT() 或CHAR() 具有一个参数或两个以上参数。 （在 MySQL 服务器中，这些函数可以采用可变数量的参数。）CONCAT() or CHAR() with one argument or more than two arguments. (In MySQL Server, these functions can take a variable number of arguments.)

BIT_COUNT()、CASE、ELT()、FROM_DAYS()、FORMAT()、IF()、MD5()、PERIOD_ADD()、PERIOD_DIFF()、TO_DAYS() 和 WEEKDAY() 函数。The BIT_COUNT(), CASE, ELT(), FROM_DAYS(), FORMAT(), IF(), MD5(), PERIOD_ADD(), PERIOD_DIFF(), TO_DAYS(), and WEEKDAY() functions.

使用 TRIM() 修剪子字符串。标准 SQL 仅支持删除单个字符。Use of TRIM() to trim substrings. Standard SQL supports removal of single characters only.

GROUP BY 函数STD()、BIT_OR()、BIT_AND()、BIT_XOR() 和 GROUP_CONCAT()。请参阅第 14.19 节“聚合函数”。The GROUP BY functions STD(), BIT_OR(), BIT_AND(), BIT_XOR(), and GROUP_CONCAT(). See Section 14.19, “Aggregate Functions”.