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SQL Server - Truncate all tables
-- COMING SOON
-----------------------------------------------------------------------------
--
-- Creates a SQL command to truncate all the required tables.
-- It removes all constraints, truncate the tables and add the same constraints again.
--
-- Based on (with a lot of fixes to work with different schemas and other issues):
-- http://sqlhints.com/2014/09/28/truncate-allall-except-fewspecified-tables-of-a-database-in-sql-server/
--
-----------------------------------------------------------------------------
USE [Cpr_Medical_E73]
GO
SET NOCOUNT ON
GO
--Get the list of all the tables to be truncated
DECLARE @TablesToBeTruncated AS TABLE (
Id INT IDENTITY(1,1),
TableObjectId INT,
TableName SYSNAME,
SchemaId INT
)
INSERT INTO @TablesToBeTruncated (TableObjectId, TableName, SchemaId)
SELECT
ST.object_id,
ST.name,
ST.schema_id
FROM
sys.Tables ST
INNER JOIN sys.Schemas SS
ON ST.schema_id = SS.schema_id
WHERE ST.type = 'U' AND ST.NAME NOT LIKE '#%' AND ST.name <> 'sysdiagrams'
--AND SS.name IN ('') -- Specify here the comma separated schema names which tables need to be truncated
--AND ST.NAME NOT IN ('') -- Specify here the comma separated table names which needs to be truncated
--AND ST.NAME IN ('') -- Specify here the comma separated table names for which truncation is not required
PRINT 'BEGIN TRANSACTION TruncateTables'
PRINT 'BEGIN TRY'
DECLARE @DbName VARCHAR(MAX)
SELECT @DbName = db_name();
PRINT ' USE [' + @DbName + ']'
--Generate the foreignkeys drop and create back script
DECLARE
@CreateScript AS NVARCHAR(MAX),
@DropScript AS NVARCHAR(MAX)
SELECT
------------DROP SCRIPT--------------------
@DropScript = ISNULL(@DropScript,'') +
' ALTER TABLE ' + QUOTENAME(SCHEMA_NAME(FKey.schema_id)) + '.' + QUOTENAME(OBJECT_NAME(FKey.parent_object_id)) +
' DROP CONSTRAINT ' + QUOTENAME(FKey.name) + CHAR(10),
-----------CREATE BACK SCRIPT-------------
@CreateScript = ISNULL(@CreateScript,'') +
' ALTER TABLE ' + QUOTENAME(SCHEMA_NAME(FKey.schema_id)) + '.' + QUOTENAME(OBJECT_NAME(FKey.parent_object_id)) +
' ADD CONSTRAINT ' + QUOTENAME(FKey.name) +
' FOREIGN KEY ' +
'(' + STUFF(( -- Get the list of columns
SELECT ',' + QUOTENAME(COL_NAME(FKeyCol.parent_object_id, FKeyCol.parent_column_id))
FROM SYS.FOREIGN_KEY_COLUMNS FKeyCol
WHERE FKey.OBJECT_ID = FKeyCol.constraint_object_id
ORDER BY FKeyCol.constraint_column_id
FOR XML PATH('')),1,1,'') +
')' +
' REFERENCES ' + QUOTENAME(SCHEMA_NAME(Tlist.SchemaId)) + '.' + QUOTENAME(OBJECT_NAME(FKey.referenced_object_id)) +
' (' + STUFF(( -- Get the list of columns
SELECT ',' + QUOTENAME(COL_NAME(FKeyCol.referenced_object_id, FKeyCol.referenced_column_id))
FROM SYS.FOREIGN_KEY_COLUMNS FKeyCol
WHERE FKey.OBJECT_ID = FKeyCol.constraint_object_id
ORDER BY FKeyCol.constraint_column_id
FOR XML PATH('')),1,1,'') +
') ' +
-- ON UPDATE ?
CASE
WHEN update_referential_action_desc = 'CASCADE' THEN ' ON UPDATE CASCADE'
WHEN update_referential_action_desc = 'SET_DEFAULT' THEN ' ON UPDATE SET DEFAULT'
WHEN update_referential_action_desc = 'SET_NULL' THEN ' ON UPDATE SET NULL'
ELSE ''
END +
-- ON DELETE ?
CASE
WHEN delete_referential_action_desc = 'CASCADE' THEN ' ON DELETE CASCADE'
WHEN delete_referential_action_desc = 'SET_DEFAULT' THEN ' ON DELETE SET DEFAULT'
WHEN delete_referential_action_desc = 'SET_NULL' THEN ' ON DELETE SET NULL'
ELSE ''
END + CHAR(10)
FROM
@TablesToBeTruncated Tlist
INNER JOIN SYS.FOREIGN_KEYS FKey
ON Tlist.TableObjectId = FKey.referenced_object_id
--PRINT THE TRUNCATION SCRIPT
IF LEN(ISNULL(@DropScript,'')) > 0
BEGIN
PRINT CHAR(10) + CHAR(10) + ' --------DROP FOREIGN KEY CONSTRAINTS SCRIPT--------'
PRINT CAST((@DropScript + CHAR(10) + CHAR(10)) AS NTEXT)
END
PRINT ' --------TRUNCATE TABLES SCRIPT--------'
--TRUNCATE TABLES
DECLARE
@id INT,
@truncatescript NVARCHAR(MAX)
SELECT
@id = MIN(Id)
FROM
@TablesToBeTruncated
WHILE @id IS NOT NULL
BEGIN
SELECT
@truncatescript = ' TRUNCATE TABLE ' + QUOTENAME(SCHEMA_NAME(SchemaId)) + '.' + QUOTENAME(TableName)
FROM
@TablesToBeTruncated
WHERE
Id = @id
PRINT CAST(@truncatescript AS NTEXT)
SELECT
@id = MIN(Id)
FROM
@TablesToBeTruncated
WHERE Id > @id
END
IF LEN(ISNULL(@CreateScript,'')) > 0
BEGIN
PRINT CHAR(10)
PRINT ' --------CREATE BACK THE FOREIGN KEY CONSTRAINTS SCRIPT--------'
PRINT CAST((@CreateScript + CHAR(10) + CHAR(10)) AS NTEXT)
END
PRINT ' COMMIT TRANSACTION TruncateTables'
PRINT 'END TRY'
PRINT 'BEGIN CATCH'
PRINT ' ROLLBACK TRANSACTION TruncateTables'
PRINT 'END CATCH'
GO
@hawatako

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@hawatako hawatako commented Nov 26, 2020

Hi, you query is very useful, Is there a way to truncate all tables a database without the list of the tables?

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