1. MySQL是否支持IF NOT EXISTS语法在创建触发器时是的,MySQL支持在创建触发器时使用IF NOT EXISTS语法。这可以防止在触发器已经存在的情况下尝试重新创建它,从而避免错误。 2. 创建触发器的基本SQL模板 创建一个触发器的基本SQL模板如下: sql CREATE TRIGGER trigger_name { BEFORE | AFTER } { INSERT | UPDATE...
CREATE TRIGGER 运行完成后,event_group还将充当宏,将它涉及的事件类型添加到 sys.trigger_events 目录视图中。 NOT FOR REPLICATION 适用于:SQL Server 2008 (10.0.x) 及更高版本。 指明触发器不得在复制代理修改触发器涉及的表时运行。 sql_statement
-- SQL Server Syntax-- Trigger on an INSERT, UPDATE, or DELETE statement to a table or view (DML Trigger)CREATE[ORALTER]TRIGGER[schema_name. ]trigger_nameON{ table | view } [WITH<dml_trigger_option>[ ,...n ] ] {FOR|AFTER|INSTEADOF} { [INSERT] [ , ] [UPDATE] [ , ] [DELETE...
DELETE (Transact-SQL) DENSE_RANK (Transact-SQL) DENY (Transact-SQL) DIFFERENCE (Transact-SQL) DISABLE TRIGGER (Transact-SQL) DROP 语句 (Transact-SQL) ELSE (IF...ELSE) (Transact-SQL) ENABLE TRIGGER (Transact-SQL) ENCRYPTBYASYMKEY (Transact-SQL) ...
Description for CREATE TRIGGER (advanced) OR REPLACE Specifies to replace or change the definition for the trigger, if one exists at the current server. This option is ignored if a definition for the trigger does not exist at the current server. If the VERSION keyword is not specified, and...
If you create a trigger on a base table of a materialized view, then you must ensure that the trigger does not fire during a refresh of the materialized view. During refresh, theDBMS_MVIEWprocedureI_AM_A_REFRESHreturnsTRUE. BEFORE
TABLE (SQL Graph) TABLE IDENTITY (Property) TRIGGER TYPE USER VIEW WORKLOAD GROUP XML INDEX XML INDEX (Selective XML Indexes) XML SCHEMA COLLECTION Collations DROP Permissions Service Broker SET xQuery Download PDF Learn SQL SQL Server Save Add to Collections Add to plan Share via Facebook x...
ON DELETE CASCADE can't be defined if an INSTEAD OF trigger ON DELETE already exists on the table. For example, in the AdventureWorks2022 database, the ProductVendor table has a referential relationship with the Vendor table. The ProductVendor.BusinessEntityID foreign key references the Vendor.Bu...
Starting with SQL Server 2012 (11.x), in Azure SQL Database, and in Azure SQL Managed Instance, if any one of the specified non-key columns are varchar(max), nvarchar(max), or varbinary(max) data types, the index can be built or rebuilt using the ONLINE option. Computed columns that...
Parallelism is disabled for tables on which you have defined a trigger or referential integrity constraint. If you define a bitmap index on table: If table is nonpartitioned, then subsequent DML operations are executed serially. If table is partitioned, then Oracle limits the degree of ...