How SQL Server obtains information

Get the table for the database

SELECTobj.name tablename,schem.name Schemname,CAST(     Case          when(SELECT COUNT(1) fromSys.indexesWHERE object_id=Obj.object_id  andIs_primary_key=1)>=1  Then 1        ELSE 0    END  as BIT) HasPrimaryKey fromsys.objects objInner JoinDbo.sysindexes IDX onObj.object_id=Idx.id andIdx.indid<=1INNER JOINSys.schemas Schem onobj.schema_id=schem.schema_idwhereType='U'  andObj.name='Table name'Order  byObj.name

Gets the field name and type of the table

1, Method one

SELECT * from Information_schema.columns WHERE table_name= ' table name '

2. Method Two

Select A.name tablename, B.name colname, C.name coltype, C.length collength

From sysobjects a inner join syscolumns b
On a.id=b.id and a.xtype= ' U '
INNER JOIN systypes C
On B.xtype=c.xusertype

Where a.name= ' table name '

Law:

Table information is stored in: sys.objects

Schema information in: Sys.schemas

Index information in: sys.indexes

Column information in: sys.columns

These four are all views.

How SQL Server obtains information