In this article. This SQL Server tutorial explains how to use the IF...ELSE statement in SQL Server (Transact-SQL) with syntax and examples. Correlated subqueries : Reference one or more columns in the outer SQL statement. using if statement in sql function. Note that the conditionals, and other statements, are written in all caps, in SQL. In this example, we used the DECODE() function in the ORDER BY clause. Otherwise, the control is passed to the next statement following the END IF. The DECODE() function returned the column to sort based on the input argument. Prerequisite – MERGE Statement As MERGE statement in SQL, as discussed before in the previous post, is the combination of three INSERT, DELETE and UPDATE statements. So if there is a Source table and a Target table that are to be merged, then with the help of MERGE statement, all the three operations (INSERT, UPDATE, DELETE) can be performed at once.. A simple example will clarify … In SQL Server, the IF...ELSE statement is used to execute code when a condition is TRUE, or execute different code if the condition evaluates to FALSE. Summary: in this tutorial, you will learn how to use the PL/SQL IF statement to either execute or skip a sequence of statements based on a specified condition.. ; Second, specify the code that will execute if the condition evaluates to TRUE. If it evaluates to true, the statement associated with THEN is executed. In the next session, we have thoroughly discussed the above topics. Ask Question Asked 9 years, 9 months ago. With the IF statement, we first check a condition. The IF statement allows you to either execute or skip a sequence of statements, depending on a condition. Applies to: SQL Server (all supported versions) Azure SQL Database Azure SQL Managed Instance Azure Synapse Analytics Parallel Data Warehouse Imposes conditions on the execution of a Transact-SQL statement. Take a look at the following example. The subquery is known as a correlated subquery because the subquery is related to the outer SQL statement. https://www.sqlshack.com/sql-if-statement-introduction-and-overview The IF statement has the three forms: – IF THEN – IF THEN ELSE – IF THEN ELSIF PL/SQL IF THEN statement Code language: SQL (Structured Query Language) (sql) In this syntax: First, specify a condition to execute the code between the IF-THEN and END IF.If the condition evaluates to TRUE, the statements between IF-THEN and END IF will execute. I have done the following: create or replace Trigger MYTRIGGER After Insert On Table1 Referencing Old As "OLD" New As "NEW" For Each Row Begin Declare Counter Int; Select Count(*) From Table2 Where Table2. In this case, the DECODE() function returned the salary column, therefore, the result set was sorted by salary column.. 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