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MySQL 教程

MySQL 主页 MySQL 简介 MySQL RDBMS

MySQL SQL

MySQL SQL MySQL SELECT MySQL WHERE MySQL AND, OR, NOT MySQL ORDER BY MySQL INSERT INTO MySQL NULL 值 MySQL UPDATE MySQL DELETE MySQL LIMIT MySQL MIN 和 MAX MySQL COUNT, AVG, SUM MySQL LIKE MySQL 通配符 MySQL IN MySQL BETWEEN MySQL 别名 MySQL 连接 MySQL INNER JOIN MySQL LEFT JOIN MySQL RIGHT JOIN MySQL CROSS JOIN MySQL 自连接 MySQL UNION MySQL GROUP BY MySQL HAVING MySQL EXISTS MySQL ANY, ALL MySQL INSERT SELECT MySQL CASE MySQL 空值函数 MySQL 注释 MySQL 运算符

MySQL 数据库

MySQL 创建数据库 MySQL 删除数据库 MySQL 创建表 MySQL 删除表 MySQL 修改表 MySQL 约束 MySQL 非空 MySQL 唯一 MySQL 主键 MySQL 外键 MySQL 检查 MySQL 默认值 MySQL 创建索引 MySQL 自动递增 MySQL 日期 MySQL 视图

MySQL 参考

MySQL 数据类型 MySQL 函数
字符串函数 ASCII CHAR_LENGTH CHARACTER_LENGTH CONCAT CONCAT_WS FIELD FIND_IN_SET FORMAT INSERT INSTR LCASE LEFT LENGTH LOCATE LOWER LPAD LTRIM MID POSITION REPEAT REPLACE REVERSE RIGHT RPAD RTRIM SPACE STRCMP SUBSTR SUBSTRING SUBSTRING_INDEX TRIM UCASE UPPER 数值函数 ABS ACOS ASIN ATAN ATAN2 AVG CEIL CEILING COS COT COUNT DEGREES DIV EXP FLOOR GREATEST LEAST LN LOG LOG10 LOG2 MAX MIN MOD PI POW POWER RADIANS RAND ROUND SIGN SIN SQRT SUM TAN TRUNCATE 日期函数 ADDDATE ADDTIME CURDATE CURRENT_DATE CURRENT_TIME CURRENT_TIMESTAMP CURTIME DATE DATEDIFF DATE_ADD DATE_FORMAT DATE_SUB DAY DAYNAME DAYOFMONTH DAYOFWEEK DAYOFYEAR EXTRACT FROM_DAYS HOUR LAST_DAY LOCALTIME LOCALTIMESTAMP MAKEDATE MAKETIME MICROSECOND MINUTE MONTH MONTHNAME NOW PERIOD_ADD PERIOD_DIFF QUARTER SECOND SEC_TO_TIME STR_TO_DATE SUBDATE SUBTIME SYSDATE TIME TIME_FORMAT TIME_TO_SEC TIMEDIFF TIMESTAMP TO_DAYS WEEK WEEKDAY WEEKOFYEAR YEAR YEARWEEK 高级函数 BIN BINARY CASE CAST COALESCE CONNECTION_ID CONV CONVERT CURRENT_USER DATABASE IF IFNULL ISNULL LAST_INSERT_ID NULLIF SESSION_USER SYSTEM_USER USER VERSION

MySQL 示例

MySQL 示例 MySQL 编辑器 MySQL 问答 MySQL 练习 MySQL 证书

MySQL 示例

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MySQL SELECT

SELECT 列 SELECT * SELECT DISTINCT SELECT COUNT(DISTINCT column_name)

示例解释

MySQL WHERE

WHERE 子句 文本字段与数值字段

示例解释

MySQL AND, OR 和 NOT

AND OR 另一个 OR NOT 组合 AND 和 OR 组合 AND 和 NOT

示例解释

MySQL ORDER BY

ORDER BY ORDER BY DESC 按多个列排序 按多个列排序 + ASC 和 DESC

示例解释

MySQL NULL 值

IS NULL 运算符 IS NOT NULL 运算符

示例解释

MySQL LIMIT

LIMIT LIMIT 与 WHERE

示例解释

MySQL MIN() 和 MAX()

MIN() MAX()

示例解释

MySQL COUNT()、AVG() 和 SUM()

COUNT() AVG() SUM()

示例解释

MySQL LIKE

选择所有以“a”开头的表行 选择所有以“a”结尾的表行 选择所有表中包含“or”的表行 选择所有第二位为“r”的表行 选择所有以“a”开头并以“o”结尾的表行 选择所有以“a”开头且长度至少为 3 个字符的表行 选择所有不以“a”开头的表行

示例解释

MySQL 通配符

% 通配符 _ 通配符

示例解释

MySQL IN

IN NOT IN IN 与 SELECT

示例解释

MySQL BETWEEN

BETWEEN NOT BETWEEN BETWEEN 与 IN BETWEEN 文本值 NOT BETWEEN 文本值 BETWEEN 日期值

示例解释

MySQL 别名

列的别名 两个别名 包含多个列的别名 表的别名

示例解释

MySQL 联接

INNER JOIN - 联接两个表 INNER JOIN - 联接三个表 LEFT JOIN RIGHT JOIN CROSS JOIN 自联接

示例解释

MySQL UNION

UNION UNION ALL UNION 与 WHERE UNION ALL 与 WHERE

示例解释

MySQL GROUP BY

GROUP BY GROUP BY 和 ORDER BY GROUP BY 与 JOIN

示例解释

MySQL HAVING

HAVING 和 GROUP BY HAVING 和 ORDER BY HAVING 和 WHERE

示例解释

MySQL EXISTS

EXISTS - 价格小于 20 EXISTS - 价格等于 20

示例解释

MySQL ANY 和 ALL

ANY - 示例 1 ANY - 示例 2 ANY - 示例 3 ALL - 示例 1 ALL - 示例 2

示例解释

MySQL CASE

CASE 1 CASE 2

示例解释

MySQL 注释

单行注释 单行注释在行尾 单行注释以忽略语句 多行注释 多行注释以忽略多个语句

示例解释

MySQL 数据库

MySQL 数据库教程请点击这里

创建 MySQL 数据库 删除 MySQL 数据库 创建 MySQL 表 删除 MySQL 表 MySQL 修改表 MySQL 约束 MySQL 非空 MySQL 唯一 MySQL 主键 MySQL 外键 MySQL 检查 MySQL 默认值 创建 MySQL 索引 MySQL 自增 MySQL 日期 MySQL 视图


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