Some knowledge points about SQL Server

2. Methods for how to open xp_cmdshell:

   exec sp_configure ' show advanced option ', 1
   Reconfigure
   Go
   exec sp_configure ' xp_cmdshell ', 1
   Reconfigure
   Go

4. About Intercepting table field names:

   Select Newname=left (Trim (name), 1) from student

6. SQL Temp Table Usage:

   SELECT * Into #A the FROM student inserts student content into the staging table #a

8. SQL Add Table Foreign Key association:
   ALTER TABLE borrow ADD constraint fk_student foreign key (STUID) references student (STUID)
10. SQL multi-Table query:

    Select Stuent.stuname,stuent.stuid,book.title,book. Bid,borrow. T_time from Student,book,borrow where Student.stuid=borrow.stuid,book. Bid=borrow. Bid,borrow. T_time between ' 2007-12-15 ' and ' 2008-1-8 '

12. SQL adds the corresponding ordinal number based on the number of table data:

    Update Stu
    Set Scount =
    (Select Temp.value from (select SCode, value = $ * row_number () over [order by SCode] from Stu) as Temp where Temp.scode = Stu.scode)

14. SQL to create clustered and nonclustered indexes:

    CREATE CLUSTERED INDEX ix_id on person (Id)

    Create nonclustered index ix_name on person (Name)--Creating a nonclustered index

Some knowledge points about SQL Server