You asked: How do I use if else in MySQL?

The syntax for the IF-THEN-ELSE statement in MySQL is: IF condition1 THEN {… statements to execute when condition1 is TRUE…} [ ELSEIF condition2 THEN {…

How do you do if else in MySQL?

MySQL IF Statement

  1. 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. …
  2. Second, specify the code that will execute if the condition evaluates to TRUE .

Can I use if condition in MySQL query?

The MySQL IF() function is used for validating a condition. The IF() function returns a value if the condition is TRUE and another value if the condition is FALSE. The IF() function accepts one parameter which is the condition to be evaluated. …

How do you add an IF statement to a query?

The IF/THEN/ELSE construct you are using is only valid in stored procedures and functions. Your query will need to be restructured because you can’t use the IF() function to control the flow of the WHERE clause like this.

How do I declare a variable in MySQL?

Declaring variables

  1. First, specify the name of the variable after the DECLARE keyword. The variable name must follow the naming rules of MySQL table column names.
  2. Second, specify the data type and length of the variable. …
  3. Third, assign a variable a default value using the DEFAULT option.
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How do I create a function in MySQL workbench?

The syntax to create a function in MySQL is: CREATE FUNCTION function_name [ (parameter datatype [, parameter datatype]) ] RETURNS return_datatype BEGIN declaration_section executable_section END; function_name.

How write if exists in SQL Server?

The following code does the below things for us:

  1. First, it executes the select statement inside the IF Exists.
  2. If the select statement returns a value that condition is TRUE for IF Exists.
  3. It starts the code inside a begin statement and prints the message.

How do I count if in MySQL?

SELECT [DISTINCT] COUNT([DISTINCT] IF(<condition>, <expression>, NULL)) AS alias_name FROM your_table_name; The syntax shows that: COUNT() function includes IF() function, which has a condition specified. If the <condition> is true, then the count will be calculated based on <expression> passed.

Does SQL have if statements?

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 do I declare in SQL?

The DECLARE statement initializes a variable by assigning it a name and a data type. The variable name must start with the @ sign. In this example, the data type of the @model_year variable is SMALLINT . By default, when a variable is declared, its value is set to NULL .

How do you declare a variable?

To declare a variable is to create the variable. In Matlab, you declare a variable by simply writing its name and assigning it a value. (e.g., ‘jims_age = 21;’). In C, Java you declare a variable by writing its TYPE followed by its name and assigning it a value.

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How do you assign a value to a variable in SQL?

To assign a value to a variable, use the SET statement. This is the preferred method of assigning a value to a variable. A variable can also have a value assigned by being referenced in the select list of a SELECT statement.