Check Constarint in SQL

Question

Please tell me how to make the query of Check Constraint?

Satyapriya Nayak · Answer

CHECK Constraint The CHECK constraint is used to limit the value range that can be placed in a column. If you define a CHECK constraint on a single column it allows only certain values for this column. If you define a CHECK constraint on a table it can limit the values in certain columns based on values in other columns in the row. SQL CHECK Constraint on CREATE TABLE The following SQL creates a CHECK constraint on the "P_Id" column when the "Persons" table is created. The CHECK constraint specifies that the column "P_Id" must only include integers greater than 0. CREATE TABLE Persons ( P_Id int NOT NULL CHECK (P_Id>0), LastName varchar(255) NOT NULL, FirstName varchar(255), Address varchar(255), City varchar(255) ) Please refer the below links http://www.w3schools.com/sql/sql_check.asp http://msdn.microsoft.com/en-us/library/ms188258%28v=sql.105%29.aspx http://www.databasejournal.com/features/mssql/article.php/3811831/Using-Check-Constraints-to-Validate-Data-in-SQL-Server.htm Thanks