How do I do an IF THEN statement in SQL?

CAN YOU DO IF statements in SQL?

IF statements can be used to conditionally enter into some logic based on the status of a condition being satisfied. The IF statement supports the use of optional ELSE IF clauses and a default ELSE clause. … An END IF clause is required to indicate the end of the statement.

How use multiple IF condition in SQL query?

If you are checking conditions against multiple variables then you would have to go for multiple IF Statements, Each block of code will be executed independently from other blocks. ELSE IF(@ID IS NOT NULL AND @ID in (SELECT ID FROM Places)) — Outer Most Block ELSE IF BEGIN SELECT @MyName = Name … …

How does case work in SQL?

Summary:

  1. CASE WHEN is used to determine conditional statements in SQL. CASE declares the start of the conditions. WHEN declares a condition. THEN declares the return of a true condition. …
  2. You can have a multitude of WHEN statements.
  3. AS can be used to create a header for the return data, otherwise it is given the header “case”
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How many else clauses can an if statement have?

When you want to define more than two blocks of statements, use the ElseIf Statement. You can nest up to ten levels of If… Then… Else statements. If you need to create an expression with more than ten levels, you must redefine it using the ElseIf statement or the Select Case…

Can I use case in where clause SQL Server?

CASE STATEMENT IN WHERE CLAUSE:

We can use a case statement in Where, Order by and Group by clause. … So, by using a CASE statement with the where condition displays the result.

Can we use 2 where clause in SQL?

Example – Two Conditions in the WHERE Clause (OR Condition)

You can use the OR condition in the WHERE clause to test multiple conditions where the record is returned if any one of the conditions are met.

How do I get a count in SQL query?

SQL COUNT() Function

  1. SQL COUNT(column_name) Syntax. The COUNT(column_name) function returns the number of values (NULL values will not be counted) of the specified column: …
  2. SQL COUNT(*) Syntax. The COUNT(*) function returns the number of records in a table: …
  3. SQL COUNT(DISTINCT column_name) Syntax.

How do I SELECT multiple values in SQL?

The IN operator allows you to specify multiple values in a WHERE clause. The IN operator is a shorthand for multiple OR conditions.

How do you do not in SQL?

Overview. The SQL Server NOT IN operator is used to replace a group of arguments using the <> (or !=) operator that are combined with an AND. It can make code easier to read and understand for SELECT, UPDATE or DELETE SQL commands.

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Can we use and in case statement in SQL?

CASE must include the following components: WHEN , THEN , and END . ELSE is an optional component. You can make any conditional statement using any conditional operator (like WHERE ) between WHEN and THEN . This includes stringing together multiple conditional statements using AND and OR .

How many tables can be join in SQL query?

Theoretically, there is no upper limit on the number of tables that can be joined using a SELECT statement. (One join condition always combines two tables!) However, the Database Engine has an implementation restriction: the maximum number of tables that can be joined in a SELECT statement is 64.

How do you write a multiple case statement in SQL SELECT query?

You can get a nearly identical runtime and query plan by writing the query like this: SELECT (case A. column1 when ‘1’ then (select value from B where B. clientId=100 and ‘1’=B.Id) when ‘2’ then (select value from C where C.

What is the difference between case and if in SQL?

IF is a control of flow statement; it indicates which T-SQL statement to evaluate next, based on a condition. CASE is a function — it simply returns a value. The main difference between the two is that if you use 12 nested ifs, you’ll be doing 12 selects, whereas you’ll only do one select with the case statement.

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