通过在 MERGE 语句中指定OPTION (<query_hint>)子句,可以强制使用某种特定联接。 建议不要将哈希联接用作 MERGE 语句的查询提示,因为该联接类型不使用索引。 有关参数化的最佳做法 如果在没有参数的情况下执行 SELECT 、 INSERT 、 UPDATE 或 DELETE 语句, SQL Server 查询优化器可能会选择在内部参数化语句。 也...
MERGE INTO [your table-name] [rename your table here] 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...
在sql server中,不能使用dual这个系统变量来创建表,所以只能换下思路用union all组装数据或使用临时表,另外using中可以使用的还有table表,view视图,sub_query子查询 USING ( SELECT'1001'C1,2C2 union all SELECT'1002'C1,3C2 union all... ) T2 工作中的一个实例 publicMessage Saves(List<GoodsQuestionManage...
https://docs.microsoft.com/zh-cn/powerquery-m/table-join https://blog.crossjoin.co.uk/2020/06/07/optimising-the-performance-of-power-query-merges-in-power-bi-part-3-table-join-and-sortmerge/ https://radacad.com/power-query-library-of-functions-shared-keyword...
There are currently two options to access a SQL Database in a function. First is the Azure SQL output binding. It's currently limited to C#, and only offers replace mode. Second is to compose a SQL query to be submitted via the appropriate SQL driver (Microsoft.Data.SqlClient for .NET...
)[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 ! ] ...
Otherwise, the query returns a NON_LAST_NOT_MATCHED_CLAUSE_OMIT_CONDITION error. WHEN NOT MATCHED BY SOURCE [ AND not_matched_by_source_condition ] Applies to: Databricks SQL Databricks Runtime 12.2 LTS and above WHEN NOT MATCHED BY SOURCE clauses are executed when a target row does not ...
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 ! ] ...
Otherwise, the query returns a NON_LAST_NOT_MATCHED_CLAUSE_OMIT_CONDITION error. WHEN NOT MATCHED BY SOURCE [ AND not_matched_by_source_condition ] Applies to: Databricks SQL Databricks Runtime 12.2 LTS and above WHEN NOT MATCHED BY SOURCE clauses are executed when a target row does not...
Query Max mem: 3112960KB Query estimated mem: 7225KB Parser runtime: 0.063 ms Planner runtime: 1.330 ms Unique SQL Id: 2643260924 (54 rows) 此语句的执行特征如下 UNION ALL 上面分支关联时,只读取public.t上的非更新列列a和d UNION ALL 下面分支关联时,只用读取public.t上的关联列列a ...