create view vw_studentsumresult as#if not exists不可写,会报错 select studentname,gradename,subjectname,examdate,studentresult from result r join student s on r.studentno=s.studentno join course c on r.subjectno=c.subjectno join grade g on c.gradeid=g.gradeid where examdate= ( select ...
does not happen on 5.1-wl5370, INSERT is not done there now, although it might change (bug#55474seems to be related).How to repeat:--disable_warnings DROP TABLE IF EXISTS t; DROP VIEW IF EXISTS v; CREATE TABLE t ( i INT ); CREATE VIEW v AS SELECT * FROM t; CREATE TABLE IF ...
1 CREATE VIEW test_view_1 AS SELECT `name` FROM t_user;2 CREATE VIEW test_view_2(username) AS SELECT `name` FROM t_user;3 CREATE VIEW test_view_3 (username, userage, usersex) AS SELECT t_user.`name`, t_user_info.age, t_user_info.sexFROM t_user, t_user_info...
CREATE DATABASE /!32312 IF NOT EXISTS/ sys /*!40100 DEFAULT CHARACTER SET utf8 */; USE sys; -- -- Temporary table structure for view host_summary DROP TABLE IF EXISTS host_summary; /!50001 DROP VIEW IF EXISTS host_summary/; SET @saved_cs_client = @@character_set_client; SET charac...
mysql> create table test01 (id int);Query OK, 0 rows affected (0.08 sec)2.不指定if not exists语句,创建test01表 mysql> create table test01 (id int);ERROR 1050 (42S01): Table 'test01' already exists 备注:如果不指定if not exists语句,创建同名表的时候就会报错.3.指定if not exists语句...
CREATE TABLE IF NOT EXISTS 表名 ( 代码语言:txt 复制 列名 数据类型, 代码语言:txt 复制 ... ); 代码语言:txt 复制 这样,如果同名表已存在,Mysql会忽略创建表的操作,不会报错。 推荐的腾讯云相关产品:腾讯云数据库MySQL 腾讯云数据库MySQL是一种高性能、可扩展的关系型数据库服务,提供了稳定可...
11CREATE[OR REPLACE][ALGORITHM = {UNDEFINED | MERGE | TEMPTABLE}]VIEW[IF NOT EXISTS]view_name[(column_list)]AS select_statement[WITH [CASCADED | LOCAL]CHECK OPTION] ALTER[ALGORITHM = {UNDEFINED | MERGE | TEMPTABLE}]VIEW view_name[(column_list)]AS select_statement[WITH [CASCADED | LOCAL]...
CREATE TABLE IF NOT EXISTS `hospital_tess`.`insurance` ( `ins_id` INT NOT NULL, `ins_name` VARCHAR(45) NULL, `ins_phone` INT NULL, PRIMARY KEY (`ins_id`)) ENGINE = InnoDB; -- --- -- Table `hospital_tess`.`payment` -- --- CREATE TABLE IF NOT EXISTS ...
修改: #方式一:create [or replace] view 视图名称[(列名列表)] as select语句[with | cascaded | local] check option] #方式二:alter view 视图名称[(列名列表)] as select语句[with [cascaded | local] check option]删除: drop view [if exists] 视图名称 [,视图名称]......
CREATE TABLE my_table ( id INT PRIMARY KEY, name VARCHAR(100) UNIQUE, age INT ); INSERT INTO my_table (id, name, age) VALUES (1, 'John', 25) ON DUPLICATE KEY UPDATE age = 25; INSERT INTO my_table (id, name, age) VALUES (2, 'Jane', 30) ON DUPLICATE KEY UPDATE age = 3...