mysql create table primary key auto_increment mysql> create table ss(id intunsignednot nullprimary key auto_increment, user_namevarchar(15)not null); Query OK, 0 rows affected (0.00 sec) mysql> mysql>insert into ss(id,user_name) values(1, 'jojo'); Query OK, 1 row affected (0.00 sec...
Introduction to MySQL ALTER TABLE statement#You use the ALTER TABLE statement to change the structure of existing tables. The ALTER TABLE statement allows you to add a column, drop a column, change the data type of column, add primary key, rename table, and many more. The following ...
CREATE TABLE emp{ emp_id INT PRIMARY KEY AUTO INCREMENT, UNIQUE INDEX uk_idx_name(emp_name[3]) }; 方式二:在创建表之后创建索引 ALTER TABLE tab_name ADD UNIQUE INDEX uk_idx (col_list); 或 CREATE UNIQUE INDEX uk_idx ON tab_name (col_list); 4.8.3查看索引 方式一:通过查看表信息来查看...
Bug #60886 ALTER IGNORE TABLE ADD PRIMARY KEY fails on duplicate key values Submitted: 15 Apr 2011 20:56Modified: 16 Apr 2011 19:35 Reporter: tom worster Email Updates: Status: Duplicate Impact on me: None Category: MySQL ServerSeverity: S2 (Serious) Version: 5.5.11OS: MacOS (10.7....
一、Table & SQL Connectors 1、概述 2、支持的外部连接 3、使用示例:kafka 4、Transform table connector/format resources 5、Schema Mapping 6、Metadata 7、Primary Key 8、Time Attributes 9、Proctime Attributes 10、Rowtime Attributes 11、完整示例 1)、建表 2)、测试数据 3)、展示结果 12、SQL Types 二...
ALTER TABLE table ADD [COLUMN] column_name_1 column_1_definition [FIRST|AFTER existing_column], ADD [COLUMN] column_name_2 column_2_definition [FIRST|AFTER existing_column], ...; 在某些情况下,您希望在添加列之前检查表中是否已存在列。但是,没有ADD COLUMN IF NOT EXISTS可用的声明。幸运的是,...
[USER ERROR] Target table has no primary key. 目标实时表没有主键列,请联系技术支持。 20022 [USER ERROR] Must and only contains AND joined EQUAL-TO predicates of all columns within the primary key: 严格的DELETE where条件检查,请联系技术支持更改系统配置。 20023 [USER ERROR] column was not foun...
mysql> CREATE TABLESPACE `ts2` ADD DATAFILE 'ts2.ibd' FILE_BLOCK_SIZE = 8192 Engine=InnoDB; mysql> CREATE TABLE t4 (c1 INT PRIMARY KEY) TABLESPACE ts2 ROW_FORMAT=COMPRESSED KEY_BLOCK_SIZE=8; 1. 2. 3. If you do not specifyFILE_BLOCK_SIZEwhen creating a general tablespace,FILE_BLOCK...
A.PRIMARYKEY B.FOREIGNKEY C.UNIQUE D.NOTNULL E.DEFAULT F.AUTO_INCREMENT 3.在创建MySQL表时,以下哪些是用于定义表结构的语句? A.CREATETABLE B.INSERTINTO C.SELECTINTO D.UPDATE E.DELETE F.ALTERTABLE 4.在MySQL中,以下哪些是用于创建索引的语句? A.CREATEINDEX B.INDEX C.UNIQUEINDEX D.KEY E.FULL...
B.ALTERTABLEC.PRIMARYKEYD.UNIQUEE.FOREIGNKEY6.以下哪些是MySQL数据库备份的策略?()A.全量备份B.增量备份C.差量备份D.定时备份E.热备份7.以下哪些是MySQL数据库安全性的措施?()A.设置强密码B.限制IP访问C.数据加密D.数据脱敏E.数据备份8.在MySQL中,以下哪些是用户权限的类型?()...