I would like to insert data into my database if one value doesn't exist in my database. I've got this code: try { SQLConnection.Open(); string sql = "INSERT INTO shop (title, price, information) values (@chp1, @chp2,@chp3)"; SqlCommand cmd = new SqlCommand(sql, SQLConnection...
INSERT INTO pay_namelist_temp ( `batchno`, `idserial`, `useranme`, `payproid`, `subpayproid`, `impdate`, `paystatus`, `payamt`, `status`, `orgcode`, `orderno`, `reservestr1`, `reservestr2`) VALUES ( '201712251109117', '104', '测4', '276', NULL, '2017-12-25 11:09...
1.INSERTINTO IF EXISTS 1.1.语法 INSERT INTO TABLE (field1, field2, fieldn) SELECT'field1','field2','fieldn'FROMDUALWHERENOT EXISTS (SELECTfieldFROMTABLEWHEREfield = ?) 1.2.插入一条记录 先创建一张表 CREATE TABLE `pay_namelist` (`id` int(11) NOT NULL AUTO_INCREMENT COMMENT '主键ID',...
So in short I insert new records with new "Appointment no" into "table 1" and the duplicate appointment no which already exist in table 1 , into table 1_copy. I could figure out the insert into if NOT EXISTS PART but am struggling to capture the dups and insert into...
1、方法一 IFNOTEXISTS(SELECT*FROMTABLE_NAMEWHEREFILED1=1)THEN INSERTINTOTABLE_NAMEVALUES(1 2、将要插入的数据先写入临时表，然后用 INSERTINTOTABLE_NAME SELECT*FROM#TEMP_TABLEALEFTJOINTABLE_NAMEONA.FILED1=B.FIELD1WHERE B.FILED1ISNULL ...
replace into...即插入数据时,如果数据存在,则删除再插入,前提条件同上,插入的数据字段需要设置主键或唯一索引,测试SQL语句如下,当插入本条记录时,MySQL数据库会首先检索已有数据(idx_username索引),...如果存在,则先删除旧数据,然后再插入,如果不存在,则直接插入: 4、insertif not exis...
方案1,前置not exists IFNOTEXISTS(SELECT1FROM[dbo].[geo_asso_type]WHERE[geo_asso_type_id]=11)BEGININSERTINTO[dbo].[geo_asso_type]([geo_asso_type_id],[bound_asso_type],[updated_date])VALUES(11,'Province to City',GETDATE())END ...
答案:可以通过使用 EXISTS 条件句防止插入重复记录。 示例一:插入多条记录 假设有一个主键为 client_id 的 clients 表,可以使用下面的语句: Code: INSERT INTO clients (client_id, client_name, client_type) SELECT supplier_id, supplier_name, 'advertising' FROM suppliers WHERE not exists (select * from...
上述代码中,首先使用INSERT INTO … SELECT …语句插入数据,并使用WHERE子句来进行判断,如果数据不存在则插入数据。然后使用ON DUPLICATE KEY UPDATE子句,在重复时执行更新操作,将重复数据的字段更新为新的值。 状态图 下面是一个使用状态图表示的示例,展示了"insert if not exists"的过程: ...
INSERT INTO clients (client_id, client_name, client_type) SELECT 10345, 'IBM', 'advertising' FROM dual WHERE not exists (select * from clients where clients.client_id = 10345); 使用dual做表名可以让你在 select 语句后面直接跟上要插入字段的值,即使这些值还不存在当前表中。