The DEFAULT constraint in SQL is used to provide a default value for a column when no value is specified […]

The CHECK constraint is used to limit the value range that can be placed in a column. If the condition

A foreign key is used to link records in two tables. It acts as a reference between the primary key

A Primary Key is a column (or a set of columns) that uniquely identifies each row in a table. It

The UNIQUE constraint ensures that all values in a column are different. It’s useful when you want to avoid duplicate

The NOT NULL constraint ensures that a column cannot have a NULL value. This means that every time you insert

SQL constraints are rules applied to table columns to ensure the accuracy, validity, and integrity of the data. Constraints are

The ALTER TABLE command allows you to make changes to an existing table’s structure without deleting or recreating it. This

The DROP TABLE command is used to permanently delete a table from a database. This removes not just the data,

The CREATE TABLE statement is used in SQL to define a new table and its columns. When creating a table,