sql server modify column

SQL server determines whether a database, table, column, or view exists. SQL server 1. Determine whether the database exists If exists (select * from sys. databases where name = 'database name ')Drop database [database name] 2. Check whether the table exists. If exists (sele

SQL Server row and column conversion Pivot UnPivotPivot is used to rotate column values to column names (row to column), and SQL Server 2000

Tags: style blog io ar os using SP for strongPivot is used to rotate column values to column names (row to column), and SQL Server 2000 can be implemented with an aggregate function with a case statementThe general syntax for pivot is: Pivot (aggregate function (

Pivot is used to rotate column values to column names (row to column), and SQL Server 2000 can be implemented with an aggregate function with a case statementThe general syntax for pivot is: Pivot (aggregate function (column) for

column on the Computecolumn table and create a nonclustered indexALTER TABLE dbo. Computecolumn Addfullname as (FirstName+"+LastName) gocreate nonclustered INDEX ix_ Compcol_citytrimon dbo. Computecolumn (FullName) GOCreate a computed column on a computecolumncompare tableALTER TABLE dbo.computecolumncompare addfullname_p as (FirstName+"+LastName) GOLast query two tables look at the results of the query pl

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

exists, the attribute belongs to the current database. If you specify the object type and name, you must also specify the parent object and type. Otherwise, SQL Server produces an error. Permission Members of the db_owner and db_ddladmin fixed database roles can add extended attributes to any object. Users can add extended attributes for their own objects. However, only db_owner can add attributes to the u

SQL Server is recommended to restore the SQL code of the sequence number of the automatic Number Column SQL Server is recommended to re-restore the SQL code for the serial number of th

Pivot is used to rotate column values to column names (row to column), and SQL Server 2000 can be implemented with an aggregate function with a case statementThe general syntax for pivot is: Pivot (aggregate function (column) for

\ ' database name \ ', \ ' autoshrink\ ', \ ' true\ '\\\ ' Add field general functionSub AddColumn (Tablename,columnname,columntype)Conn.execute (\ "Alter Table \" tablename\ "ADD \" columnname\ "\" columntype\ "\")End Sub\\\ ' Change field general functionSub Modcolumn (Tablename,columnname,columntype)Conn.execute (\ "Alter Table \" tablename\ "alter Column \" columnname\ "\" columntype\ "\")End Sub\\\ ' Check if the table existsSql=\ "SELECT COUNT

@filename =replace ( @filename, ' $ ', ') set @filename =replace (@filename, ' ', ')--filter These special characters, replace the new file name Set @newFilePath =dbo. Getdirectorypath (@filePath) + ' \ ' + @filename--New path name ( Gets the file directory dbo according to the path. Getdirectorypath method --============================================= --Author: Paul Griffin --Create Date: January - Description: Returns The path without the file name

Tags: modify password Windows Server server securitySQL Server R2 modify the sa password by logging in with SQL Server AuthenticationHere's how to fix itAfter logging in with Windows au

', n ' language ', UNION all SELECT N ' Zhang San ', N ' English ', 100 GO SELECT * FROM [Testrows2columns] (Figure 2: Sample Data) (b) First, a static way to achieve row to column, the effect of 3 is shown: --1: Static splicing row to column SELECT [UserName], SUM (case [Subject] when ' math ' then [Source] ELSE 0 END) as ' [Mat

First, backgroundThe ID field in table A in the SQL Server database is defined as: [ID] [int] IDENTITY, as the data grows, the ID value is close to 2147483647 (the value range for int is:-2 147 483 648 to 2 147 483 647). , although the old data has been archived, but the table needs to retain the most recent 100 million data, how to solve the ID value of the rapid explosion problem?There are two ways to sol

'the value of the Key5' fromheadertable awhereA.headerid= 10000 SELECTA.*, t.a0001 as 'the value of the Key1', t.a0002 as 'the value of the Key2', t.a0003 as 'the value of the Key3', t.a0004 as 'the value of the Key4', t.a0005 as 'the value of the Key5' fromHeadertable AInner Join (SelectHeaderid, Detailkey, detailvalues fromdetailtable) T Pivot (MAX(detailvalues) forDetailkeyinch(a0001,a0002,a0003,a0004,a0005)) T onT.headerid=A.headeridwhereA.headerid= 10000 　　

[Username],[subje Ct],[source] from [Testrows2columns]) P-PIVOT (SUM ([Source]) for [Subject] in (' + @sql_col + ')) as Pvt ORDER by Pvt. [UserName] ' PRINT (@sql_str) EXEC (@sql_str)(vi) Maybe a lot of people come to the above step is enough, but you will find that when others get your code, you need to constantly modify the table name in his own environment, grouping columns, row To column fields, fi

I. Definition and characteristics of the identity columnThe identity column in SQL Server is also called the identifier column, which is also known as the self-increment column.This type of column has the following three characteristics :1. The data type of the

Note: SQL Server 2005 and above support. Version estimation is not supported (working environment 2005,2008).To work, you need to add a new column to the existing table in SQL Server and add a description. Thus there is a stored procedure as follows. (Attach the stored proce

) Physical fromScores--Table name Group byStuid--Group QueriesMain knowledge: Max (), Case,group by group query.Max () takes the maximum value.Case: My understanding is to choose from a few options, such as:Case course when ' language ' then score else 0 endWhen course is a language, case returns one of the corresponding score and 0, in this example, the first data is queried:0101 Languages 78At this time: course= ' language ', score=78, then case returns 78,When querying the second piece of da

Note: SQL Server 2005 and later versions are supported. This version is estimated to be not supported (working environment ). To work, you need to add a new column to the existing SQL Server table and add a description. The stored procedure is as follows (attach the stored