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What is the use of DEFAULT constraint? How can it be applied to a column while creating a table?
DEFAULT constraint is used set a default value for a column in MySQL table. If it is applied on a column then it will take the default value of not giving any value for that column. Its syntax would be as follows −
Syntax
DEFAULT default_value
Here, default_value is the default value set for the column.
Example
The query below will create a table named workers where we assign the column id a DEFAULT value 1000.
mysql> Create table workers(Name Varchar(25), Id INT NOT NULL DEFAULT 1000); Query OK, 0 rows affected (0.47 sec) mysql> Insert into workers(Name, Id) values('Ram', 101); Query OK, 1 row affected (0.04 sec) mysql> Insert into workers(Name) values('Mohan'); Query OK, 1 row affected (0.10 sec) mysql> Select * from Workers; +-------+------+ | Name | Id | +-------+------+ | Ram | 101 | | Mohan | 1000 | +-------+------+ 2 rows in set (0.00 sec)
The above result set stores the default value 1000 for id when we do not give any value for the same.
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