How if condition works in SQL?
We can understand SQL IF Statement using the following flow chart.
- The condition in SQL IF Statement should return a Boolean value to evaluate.
- We can specify a Select statement as well in a Boolean expression, but it should enclose in parentheses.
- We can use BEGIN and END in the IF Statement to identify a statement block.
What is conditional clause in SQL?
A “conditional clause” is a portion of a query that restricts the rows matched by certain conditions. In SQL, that means the WHERE or HAVING portions of a SELECT , UPDATE , or DELETE query.
Are there conditionals in SQL?
Conditional statements are used to define what logic is to be executed based on the status of some condition being satisfied.
How do you do and condition in SQL query?
The SQL AND condition and OR condition can be combined to test for multiple conditions in a SELECT, INSERT, UPDATE, or DELETE statement. When combining these conditions, it is important to use parentheses so that the database knows what order to evaluate each condition.
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.
Can we use case in where clause in SQL?
The case statement in SQL returns a value on a specified condition. We can use a Case statement in select queries along with Where, Order By, and Group By clause. It can be used in the Insert statement as well.
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 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.
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
- 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: …
- SQL COUNT(*) Syntax. The COUNT(*) function returns the number of records in a table: …
- SQL COUNT(DISTINCT column_name) Syntax.
What can SQL not do?
The SQL NOT condition (sometimes called the NOT Operator) is used to negate a condition in the WHERE clause of a SELECT, INSERT, UPDATE, or DELETE statement.