while(exists(select 1 from INFORMATION_SCHEMA.TABLE_CONSTRAINTS where CONSTRAINT_TYPE='FOREIGN KEY'))
begin
 declare @sql nvarchar(2000)
 SELECT TOP 1 @sql=('ALTER TABLE ' + TABLE_SCHEMA + '.[' + TABLE_NAME
 + '] DROP CONSTRAINT [' + CONSTRAINT_NAME + ']')
 FROM information_schema.table_constraints
 WHERE CONSTRAINT_TYPE = 'FOREIGN KEY'
 exec (@sql)
 PRINT @sql
end


while(exists(select 1 from INFORMATION_SCHEMA.TABLES 
    where TABLE_NAME != 'database_firewall_rules' 
    AND TABLE_TYPE = 'BASE TABLE'
    AND TABLE_NAME NOT IN (select name from sys.external_tables)))
begin
 declare @sql1 nvarchar(2000)
 SELECT TOP 1 @sql1=('DROP TABLE ' + TABLE_SCHEMA + '.[' + TABLE_NAME + ']')
 FROM INFORMATION_SCHEMA.TABLES
 WHERE TABLE_NAME != 'database_firewall_rules'
    AND TABLE_TYPE = 'BASE TABLE'
    AND TABLE_NAME NOT IN (select name from sys.external_tables)
exec (@sql1)
 PRINT @sql1
end