Delete all data in SQL Server database

Question

How I can delete all records from all tables of my database? Can I do it with one SQL command or I need for one SQL command per one table?

Answer 1

1. First you'll have to disable all the triggers :

   sp_msforeachtable 'ALTER TABLE ? DISABLE TRIGGER all';
   

2. Run this script : (Taken from this post Thank you @SQLMenace)

   SET NOCOUNT ON
   GO
   
   SELECT 'USE [' + db_name() +']';
   ;WITH a AS 
   (
        SELECT 0 AS lvl, 
               t.object_id AS tblID 
        FROM sys.TABLES t
        WHERE t.is_ms_shipped = 0
          AND t.object_id NOT IN (SELECT f.referenced_object_id 
                                  FROM sys.foreign_keys f)
   
        UNION ALL
   
        SELECT a.lvl + 1 AS lvl, 
               f.referenced_object_id AS tblId
        FROM a
        INNER JOIN sys.foreign_keys f ON a.tblId = f.parent_object_id 
                                      AND a.tblID <> f.referenced_object_id
   )
   SELECT 
       'Delete from ['+ object_schema_name(tblID) + '].[' + object_name(tblId) + ']' 
   FROM a
   GROUP BY tblId 
   ORDER BY MAX(lvl),1
   

This script will produce DELETE statements in proper order. starting from referenced tables then referencing ones

3. Copy the DELETE FROM statements and run them once

4. enable triggers

   sp_msforeachtable 'ALTER TABLE ? ENABLE TRIGGER all'
   

5. Commit the changes :

   begin transaction
   commit;