方法1:使用LOOP,LOOP中使用EXIT直接退出,保证只执行一次: 1declarefound boolean :=false; 2forxin(SELECT*FROMtbl_some_tableWHEREsome_condition) loop 3found :=true; 4--Do something here; 5endloop; 6IFnotfoundTHEN 7--DO something else 8ENDIF; 为了保证执行一次:可以如下 1forxin(SELECT*FROMtbl_s...
Using a different type of FOR loop, you can iterate through the results of a query and manipulate that data accordingly. The syntax is: [ <<label>> ]FORtargetINqueryLOOPstatementsENDLOOP[label]; 3.5 Looping Through Arrays The FOREACH loop iterates through the elements of an array value. Th...
If you want to use the same style but make it work, you need to add your own index/row co...
Can we optimise While Loop in sql server for large number of data? Can we pass parameters to the trigger?(Beginner) Can we RAISERROR inside MERGE Statement Can we select Bottom 1000 rows of a database Table from SSMS 2008 R2? Can we set value in a variable inside a select statement ca...
Sometimes there is a need to loop through records and process a record at a time in a Transact-SQL script or stored procedure in Microsoft SQL Server. It may not be the most efficient approach, but it may be the only option. In this tutorial, we look at how to create a WHILE loop ...
Click the Control Flow tab and double-click the Foreach Loop. In the Foreach Loop Editor dialog box, click General and, optionally, modify the name and description of the Foreach Loop. Click Collection and select an enumerator type from the Enumerator list. Specify an enumerator and set enum...
Using the<dml_table_source>argument of the INSERT statement raises a syntax error.You can capture the results of an OUTPUT clause in a nested INSERT, UPDATE, DELETE, or MERGE statement, and insert those results into a target table or view. This is done using the<dml_table_source>argument...
FOR SELECT * FROM authors Pretty simple, but it gets a bit deeper from here. There are many options available, in just this first part of the cursor, so you can just pause here to look at those options. Don't worry if they seem a bit confusing at the moment; just read through them...
Because of this error, all effects of the statement are rolled back. If the statement is aSELECTstatement, partial results or no results might be returned. Any partial results returned might not include all rows on recursion levels beyond the specified maximum recursion level. ...
The join method is appropriate for the number of rows being returned. For example, nested loop joins through indexes may not be optimal when many rows are being returned. Views are used efficiently. Look at theSELECTlist to see whether access to the view is necessary. ...