sql添加表

IF EXISTS(SELECT * FROM sysobjects WHERE name='learnRecord')
DROP TABLE learnRecord
GO
CREATE TABLE [learnRecord](
    [lid] int NOT NULL CONSTRAINT [FK_pt_learnRecord_learnSubject] REFERENCES [learnSubject]([id])ON UPDATE CASCADE ON DELETE CASCADE,
    [sid] int NOT NULL CONSTRAINT [FK_pt_learnRecord_subjectClass] REFERENCES [subjectClass]([ID])ON UPDATE CASCADE ON DELETE CASCADE,
    [stype] char(2) NULL,
    [kid] int not null,
    [answer]nvarchar(20) null,
    [result] bit null,
    [createTime] [datetime] NOT NULL DEFAULT (getdate()),
)
GO