SQL DELETE QUERY - The Coding Shala

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SQL DELETE QUERY 

The SQL 'DELETE' Query is used to delete existing rows from a table. We can use the 'WHERE' clause with 'DELETE' to delete the selected row if we don't use 'Where' then it will delete all the rows from a table. 
SQL DELETE QUERY - The Coding Shala

SQL DELETE QUERY SYNTAX 

The basic SQL DELETE query syntax is as follows - 
 DELETE FROM table_name  
 WHERE condition;

SQL DELETE QUERY EXAMPLES 

The following table Persons contains - 

PersonID     LastName     FirstName     Address     City  
 1          Saini          Akshay          A-101     Pune  
 2           last           first          A-101     Pune  
 3           null           Nikhil           null     null

The following query will delete a row that has PersonID is 3 - 

SQL >> delete from Persons  
        where  
       PersonID = 3  
 
Output >>  
 PersonID     LastName     FirstName     Address     City  
 1          Saini          Akshay        A-101     Pune  
 2           last           first       A-101     Pune

  • The following query will delete all the records from the 'Persons' table - 
 delete * from Persons


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