table structure in sql server

TABLEdbo. Orders; CREATE TABLEdbo. Orders (OrderIDINT not NULL, EmpidINT not NULL, CustIDVARCHAR(Ten) not NULL, Orderts DATETIME2 not NULL, QtyINT not NULL, CONSTRAINTPk_ordersPRIMARY KEY(OrderID)); /** Add PRIMARY KEY constraint **/ ALTER TABLEDbo. OrdersADD CONSTRAINTFk_orders_employeesFOREIGN KEY(Empid)REFERENCESdbo. Employees (Empid); /** Add default constraint **/ ALTER TABLEDbo. OrdersADD CONSTRAINTDft_orders_ordertsDEFAULT(Sysdatetime ()) forOrderts; /** Delete Check constr

table Scan is where the table was processed row by row from beginning to end. An index scan is a where the index is processed row by row from beginning to end. If The index is a clustered index then an index scan is really a table scan. Summary: In SQL Server, t

; +----+-------------+-------+-------+---------------+---------+---------+------+------+-------+ | id | select_ Type | Table | Type | possible_keys | key | key_len | ref | rows | Extra | +----+-------------+-------+-------+---------------+---------+---------+------+------+-------+ | 1 | Simple | film | index | NULL | PRIMARY | 2 | NULL | 55 | NULL | +----+-------------+-------+-------+---------------+---------+---------+

Starting with SQL Server 2005, we can support recursive queries directly through a CTE, which is a common table expressionBaidu EncyclopediaA common table expression (CTE), which is a temporary named result set that is defined in a query, is used in the FROM clause. Each CTE is defined only once (but can be referenced

above code, we can see that this table has the characteristics of the general table--there is a primary key, and the primary key is also a clustered index. As mentioned earlier, a partitioned table is a partition condition for a field, so you cannot create a clustered index other than this field. Therefore, to convert a normal

PFS Page GAM page Sgam page Keep page Keep page DCM Page BCM Page In addition to page 9th for the boot page of the database, pages 8th through 173th are related to the SQLSERVER2008 internal system tables, and then from 174th page to No. 279 page are unassigned pages. Because the first page starts at 0, it's just 280 pages, which is exactly the same size as the database data files we see.See the previous operation, database size: 2.18 MB (2,293,760

Cursors are usually used to traverse tables on SQL Server. in SQL Server, you can easily use cursors to implement loops and traverse records in tables on SQL Server. This article describes how to use

We know that SQL Server's data Row Storage has two data structures: A: heap B: B (binary Tree) Data is sorted and stored according to one of these two types. Friends who have learned the data structure should know the binary tree. Why is binary tree used? Because binary search is convenient and fast Find the data. If it is a heap, the data is not sorted in any order, and there is no

Cursors are usually used to traverse tables on SQL Server. in SQL Server, you can easily use cursors to implement loops and traverse records in tables on SQL Server. This article describes how to use

then we can break down each point of the key.Partitioning is to split a table data into sub-collections, that is, to split a data file into multiple data files, but the storage of these files can rely on a filegroup or multiple filegroups, because more than one filegroup can increase the database access concurrency, but also can be different partitions configured to different disks to improve efficiency , the recommended partition is created with the

Label:Delete the table containing the specified stringCREATE PROCEDURE Sys_deletetablebytablename (@bianliang varchar (100))AsBeginDECLARE @biao varchar (+), @sql varchar (1000)Set @sql = '% ' [email protected]+ '% 'Declare c cursor for select name from sysobjects where type= ' u ' and name @sqlSet @sql = ' drop

Recently, a project was developed to replace the data table prefix with different schemas (database architecture) when creating a database. This design makes the data table name Friendly and logically clear and more compliant with the SQL Server database specifications. However, the problem occurred yesterday when the

when @xtype= $ Then "" "+convert (char),'+@name+')+ "" " --uniqueidentifier Else @name End End End Fetch Next fromSyscolumns_cursor into @name,@xtype End CloseSyscolumns_cursordeallocateSyscolumns_cursorSet @sql='SET NOCOUNT ON select"'Insert into'+@tablename+'('+@column+') VALUES ("' as"'--"','+@columndata+',"')"' from'+@tablename Print '--'+@

statements is the same, because the two statements are indeed different from the statement sequence, if tID is an aggregationIndex, Then the last sentence will only be searched from the 10000 records in the table; in the previous sentence, you need to first look up several names = ''zhangsan'' from the entire table, and then propose the query results based on the constraints tID> 10000. In fact, such a wor

the partition field Drop Index L_testresult. Idx_l_testresult_measuretime --Create an index by partition scheme CREATE INDEX Idx_l_testresult_measuretime On L_testresult (Measuretime) On Monthdaterangescheme (Measuretime) 6. For a clustered index in a partitioned table, it is best to remove the rebuild: --Rebuilding the main building of clustered index ALTER TABLE L_testresult DROP CONSTRAINT Pk_l_testres

SQL Server sorting in the tree structure departmentBecause you want to implement the departmental sorting function, and to consider the departmental hierarchy, it is not possible to sort directly with SQL, so write a SQL function to support it.First Department

In SQL server, how can I use SQL statements to add comments to the column of a table? I didn't use SQL statements to add them before, but I added them to Enterprise Manager: (I checked the information, microsoft introduced extended attributes in

Tags: symbol ASE UTC Modify Table Master build level standard must4.2 SQL Server Database physical structureSQL Server stores all of the data in a file. These files are partitioned into sub-structures that SQL Server manages to ma

In-depth understanding of table scanning in SQL Server and SQL A long time ago when we were writing SQL, the most feared thing was that SQL was inexplicably super slow. The slow thing was that the ball was still turning back... It

amount indicated * @return array*/ Public functionGetalltablenames () {$tableNames=Array(); $sql= "Show Tables"; $cursor=$this->conn->query ($sql); foreach($cursor as $row) { $tableNames[] =$row[0]; } return $tableNames; } /** * @desc gets the table structure of a