ALL Keyword
The ALL keyword or command is used to check logical conditions.
The ALL Keyword is a logical operator that compares single value with a single-column set of values returned by a subquery.
The ALL command returns the boolean value True Or False.
Return True if all of the subquery values match the condition.
Syntax
ALL Operator with Select Query
SELECT ALL <COLUMN_NAME> FROM <TABLE_NAME> WHERE <CONDITION>;
Example
SELECT ALL Emp_Name FROM Employee WHERE Emp_Age < 30 ;
Syntax
ALL Operator with Where Clause or Having Clause,
SELECT <COLUMN_NAMES> FROM <TABLE_NAME> WHERE <COLUMN_NAME> ALL (SUBQUERY);
Example
SELECT Emp_Id,Emp_Name,Emp_Salary FROM Employee WHERE Emp_Salary > ALL (SELECT Emp_Salary FROM Employee WHERE Emp_Id = 101);
Summary
ALL Keyword returns TRUE, if all the mentioned sub-queries values meet the conditions.