--1、取得数据库所有表的默认值：select    t3.name   as   表名,t1.name   as   字段名,t2.text   as   默认值   ,t4.name     from   syscolumns   t1,syscomments   t2,sysobjects   t3   ,sysobjects   t4      where     t1.cdefault=t2.id   and   t3.xtype='u'   and   t3.id=t1.id     and   t4.xtype='d'   and   t4.id=t2.id;  --取得数据库中已有默认值的脚本select  'ALTER TABLE [' +  t3.name  + '] ADD DEFAULT ' + t2.text + ' FOR [' + t1.name + '];'   from   syscolumns   t1,syscomments   t2,sysobjects   t3   ,sysobjects   t4      where     t1.cdefault=t2.id   and   t3.xtype='u'   and   t3.id=t1.id     and   t4.xtype='d'   and   t4.id=t2.id ORDER BY t3.name, t1.name;--alter table MES_MOAppoint_ProdProcSteps  add default  (1)  for ContainerChangeOut;--2、生成删除所有默认值的语句：select 'ALTER  TABLE [' +  t3.name   + '] DROP  CONSTRAINT  ' +t4.name  +';'   from   syscolumns   t1,syscomments   t2,sysobjects   t3   ,sysobjects   t4       where     t1.cdefault=t2.id   and   t3.xtype='u'   and   t3.id=t1.id     and   t4.xtype='d'   and   t4.id=t2.id ORDER BY t3.name, t1.name;--3、生成批量添加所有默认值的语句：select 'alter table ' +  t3.name   + '  add default  (1)  for ' +t1.name  +';' from   syscolumns   t1,syscomments   t2,sysobjects   t3   ,sysobjects   t4      where     t1.cdefault=t2.id   and   t3.xtype='u'   and   t3.id=t1.id   and   t4.xtype='d'   and   t4.id=t2.id ;