You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'MODIFY column_name new_data_type' at line 1 1. 这个错误提示表明在MODIFY关键字附近存在语法错误。下面我们将介绍两种常见的导致这个问题的原因,并给出解决方法。
-- 先确保列不为空 ALTER TABLE table_name MODIFY column_name datatype NOT NULL; -- 再设置为主键 ALTER TABLE table_name ADD PRIMARY KEY (column_name); 问题3:修改列名时遇到“ERROR 1068 (42000): Multiple primary key defined” 原因:表中有多个主键定义。 解决方法: 代码语言:txt 复制 -- 先删...
11)修改字段属性 alter table 表名 modify column 字段名 类型 alter table 表名 modify column 字段1 类型,字段2 类型 例如:将class表的name列属性改成varchar(100) alter table class modify column name varchar(100); 或者: alter table 表名 change 列名 列名 varchar(100); alter table class change nam...
We can't just make up syntax. The manual (http://dev.mysql.com/doc/refman/5.7/en/alter-table.html) says ... ALTER TABLE MODIFY [COLUMN] col_name column_definition [FIRST | AFTER col_name] And while you're at it, year decimal(4,0) is not optimal; look up the year datatype, ...
MODIFY COLUMN `content` text CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci NOT NULL COMMENT '修改字符集为utf8mb4,兼容表情符' AFTER `qid`; 修改过程中锁表 ‘ 修改 锁表 不能写,可读 sou456执行 show processlist; : 7247418 sou456 116.204.67.22:64059 sou456 Query 0 starting show processli...
alter table 表名 modify column '字段名' varchar(30) character set gbk not null; //添加表字段 alter table 表名 add column '字段名' varchar (20) character set gbk; 注:执行命令过程中字段名不加引号 http://www.cnblogs.com/dongweihang/p/4126004.html ...
respectiveowners.Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.mysql> nihao;ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'nihao' at line 1...
MODIFY is more convenient to change the definition without changing the name because it requires the column name only once: ALTER TABLE t1 MODIFY b INT NOT NULL; To change a column name but not its definition, use CHANGE. The syntax requires a column definition, so to leave the definition...
Every “character” column (that is, a column of type CHAR, VARCHAR, a TEXT type, or any synonym) has a column character set and a column collation. Column definition syntax for CREATE TABLE and ALTER TABLE has optional clauses for specifying the column character set and collation: ...
| MODIFY [COLUMN] column_definition [FIRST | AFTER col_name]| DROP [COLUMN] col_name | DROP PRIMARY KEY | DROP {INDEX|KEY} index_name | DROP FOREIGN KEY fk_symbol | DISABLE KEYS | ENABLE KEYS | RENAME [TO] new_tbl_name | ORDER BY col_name [, col_name] ...| ...