Some inbuilt useful store procedures.

--Drop all table from database
EXEC sp_MSForEachTable "Drop TABLE ?"

--Delete data from all tables
EXEC sp_MSForEachTable "DELETE FROM ?"

--truncate data from all tables
EXEC sp_MSForEachTable "Truncate table ?"

--Desable all constraints
EXEC sp_msforeachtable "ALTER TABLE ? NOCHECK CONSTRAINT all"

--Enable all constraints
exec sp_msforeachtable "ALTER TABLE ? WITH CHECK CHECK CONSTRAINT all"

--we want to reseed identity
EXEC sp_MSforeachtable "DBCC CHECKIDENT ( '?', RESEED, 0)"

--Shrink Database
EXEC sp_MSForEachDB 'DBCC SHRINKDATABASE (''?'' , 0)'