SQL Server

Today read the T-SQL, see unbounded preceding, want to compare to the next row_number () running speed.SQL and related results are as follows, the data in the database is 5w+.Row_number ():SET STATISTICS on SELECT over (ORDER by DESC) Rn,id from

Https://stackoverflow.com/questions/2404565/sql-server-difference-between-partition-by-and-group-byThey ' re used in different places. group bymodifies the entire query, like:select customerId, count(*) as orderCountfrom Ordersgroup by

Clustered index and nonclustered index, in fact, there are a lot of articles have been detailed introduction.Nonclustered indexesSimply put, a clustered index is a column that is appropriate for a field that has little change (as far as possible

Backing Up the databaseSelect the database you want to back up, right-click, select Task-BackupPop Up the Backup Database window and select AddPop-up Select Backup Destination window, click Browse, select the directory where the backup database is

/*mssql--Create remote link exec sp_addlinkedserver@server= ' pacs_link ',--the server alias being accessed @srvproduct= ',--sqls Erver default does not need to write, or oracle@provider= ' SQLOLEDB ',--different libraries are not the same, the OLE

--View Current link situation:SELECT * from Sys.servers;--use sp_helpserver to display the available serversExec sp_helpserver--Delete a link that already existsExec sp_droplinkedsrvlogin Server alias, NullExec sp_dropserver Server Aliases--use

I. PRIMARY KEYPrimary key as a unique identifier in the table that identifies this column does not allow duplicate dataIf two or more columns are combined to uniquely identify each row in the table, the primary key is called the composite primary

Monitoring of Cpu,io, memory in SQL Server DB during performance testingResource usage can be viewed through the system process tableNote to have Master permissionsSelect top * from sysprocesses ORDER by CPU descSelect top * from sysprocesses ORDER

Company Sales department to statistics salesman's customers and in accordance with the name of the salesman output Excel, see the following program--Declaring the required variablesDECLARE @sql varchar ($), @TypeID varchar (6), @MyName varchar (10)--

1.SELECT and from statementsSelect indicates that the query is executed, and then it needs to know from which side to query the data, from which is the limit of the data being read in which table or tables, which makes up a basic statement.SELECT *

I. BACKGROUNDExternal companies are authorized to access our company's database, data interface calls, to give them a view of the specified view and authorized account, so in the database, to the specified user authorized access to the specified

Encountered the need to operate SQL Server servers, I even command operation will not, Baidu a half-day finally found a can use, although it is not how to use but record a better, or later in the future if you meet and need to check half a daySELECT

Transferred from: http://www.maomao365.com/?p=5416Summary:Order by means that the first column of the table is arranged in order from small to largeThen arrange the second column in order from small to largeOrder BY is equivalent to order BY [first

The following insights are diaries that are made during the process of using cursors. I am also the first time to use, if there is something wrong, please criticize, we work together.1.　　Msg 16951, Level 16, State 1, procedure Usp_proc, line 16thThe

ALTER PROCEDURE [dbo]. [Proc_updmonthstatus] As BEGIN declare @aint, @errorint, @Id varchar ( $), @Area varchar ( $), @Department varchar ( $), @Year int, @Month intSet@a=1 Set@error =0--declares that the cursor is UID declare order_cursor

Server reload system, reinstall on SQL Server, attach to previous database,Then there was a login for each database that was used to manipulate the database, and the other databases were not operational.Attached to the database after the user in the

1 //Query all indicateSelectName fromsysobjectswhereXtype='u'2 3 Select * fromsys.tables4 //Querying all table names and rows in the database5 6 SELECTA.name, B.rows7 8 fromsysobjects asAINNER JOINsysindexes asB ona.ID=b.id9 Ten WHERE(A.type= 'u')

Excerpt from:http://www.maomao365.com/?p=6612Summary:In SQL Server, SQL scripts are described below to avoid the sharing of methods with the exception of 0 errors In the development of various business systems, there are usually zero-error

Select Top -Qs.creation_time,Last_execution_time,total_physical_reads,total_logical_reads,total_logical_writes,db_name(dbid) Dbname,execution_count,--Total_worker_time,Last_worker_time,--substring (CONVERT (char), DATEADD (ms,total_worker_time/1000,

Use theGoDECLARE @TableName varchar(255);CREATE TABLE#GetRecordingTempTable ([TableName] varchar(255) not NULL,[Mrs]date);DECLARETable_cursorCURSOR For --a table containing the column ' Sigdate 'SelectA.[name]Table name fromsysobjects A, (Select [ID]