Now that we have learned how to insert records using the SQL MERGE statement, let us learn how to update the values in the same statement. In order to update the values, the ProductID field must have a common value in both the source and the target tables. Only then the database engin...
The SQL MERGE statement was introduced in the SQL Server 2008 edition which allowed great flexibility to the database programmers to simplify their messy code around the INSERT, UPDATE and DELETE statements while applying the logic to implement SCD in ETL. SQL MERGE语句是在SQL Server 2008版中引入...
mysql merge update_SQL中批量更新 merge into用法 从备份表中更新字段到正式表中,使用 UPDATE 批量更新大量的数据,会出现效率低下,有时候甚至卡死的情况,后面通过使用 MERGE INTO 代替 UPDATE 执行批量更新,会提升执行效率。 MERGE INTO语法如下: MERGE INTO table_name alias1 USING (table|view|sub_query) alia...
AND soh.OrderDate = @OrderDate GROUP BY ProductID) AS source (ProductID, OrderQty) ON (target.ProductID = source.ProductID) WHEN MATCHED AND target.Quantity - source.OrderQty <= 0 THEN DELETE WHEN MATCHED THEN UPDATE SET target.Quantity = target.Quantity - source.OrderQty, target....
USING ( [write your query here] )[rename your query-sql and using just like a table] ON ([conditional expression here] AND [...]...) WHEN MATHED THEN [here you can execute some update sql or something else ] WHEN NOT MATHED THEN [execute something else here ! ] ...
UPDATE、DELETE、INSERT操作相应的BOOLEAN类型判断条件。需要注意: 当出现三个WHEN子句时,UPDATE、DELETE、INSERT都只能出现一次。 如果UPDATE和DELETE同时出现,出现在前的操作必须包括[AND <BOOLEAN expression>]。 WHEN NOT MATCHED只能出现在最后一个WHEN子句中,并且只支持INSERT操作。
merge mytable as T using(SELECT '123' as a) N on (T.a != N.a) and T.id=2 when matched thenupdate set T.a=N.a 试试这个
DATA_DT = 20230829 AND T1.CORP_INDV_IND = 'C') WHEN MATCHED THEN UPDATE SET T1.DPS_CLS_BUZ_SIZE = T2.DPS_CLS_BUZ_SIZE; 改写完成后,该sql性能提升10倍以上。 【声明】本内容来自华为云开发者社区博主,不代表华为云及华为云开发者社区的观点和立场。转载时必须标注文章的来源(华为云社区)、文章...
SQL CREATEPROCEDUREProduction.usp_UpdateInventory @OrderDate DATETIMEASMERGEProduction.ProductInventoryAStgtUSING(SELECTProductID,SUM(OrderQty)FROMSales.SalesOrderDetailASsodINNERJOINSales.SalesOrderHeaderASsohONsod.SalesOrderID = soh.SalesOrderIDANDsoh.OrderDate = @OrderDateGROUPBYProductID )ASsrc(ProductID, ...
) Event_1ix1dzn ON (Event_1u18olr."ae_header_id" = Event_1ix1dzn."ae_header_id" AND Event_1u18olr."ae_line_num" = Event_1ix1dzn."ae_line_num") WHEN MATCHED THEN UPDATE SET "application_code" = Event_1ix1dzn."application_code", ...