t sql remove duplicates

') if exists (SELECT * from tempdb. sysobjects where id=object_id (' tempdb. #Tmp1 ')) drop table #Tmp1Select ID as autoid, * into #Tmp1 from adminif exists (SELECT * from tempdb. sysobjects where id=object_id (' tempdb. #Tmp2 ')) drop table #Tmp2Select min (autoid) as autoid into #Tmp2 from #Tmp1 Group by Username,passwordif exists (SELECT * from dbo.sysobjects WHERE id = object_id (N ' admin ') and objectproperty (Id,n ' isusertable ') = 1) Drop tabl E adminSelect Id,username,password to admi

Tags: RAC button val Pow quote field name MAT value signWhen you use PowerDesigner to generate a database to build a table SQL script, especially when the Oracle database is used, the table name is typically quoted. In fact, the quotation marks are PL/SQL specifications, the database will be strictly in accordance with the name of "" to build a table, if not ", will be based on the default set of Oracle Tab

The distinct keyword can be used to remove duplicate rows from the results of the SELECT statement. If noDistinct: All rows, including duplicate rows, are returned. For example, if you select all author IDs in titleauthorDistinct, the following rows will be returned (including some repeated rows ): Use pubsSelect au_idFrom titleauthor The following is the result set: Au_id-----------172 to 32-1176213 to 46-8915213 to 46-8915238-95-7766.267 to 41-23942

Mysql removes spaces from data SQL statement bitsCN.com SQL statement for Mysql to remove spaces from data When data is recorded, it is found that there are extra spaces behind the values in some dictionary tables. you can remove them in batches using SQL statements. J

SQL statements remove duplicate records, get duplicate records --Query a table to effectively remove duplicate records, UserID as a self-growing primary key, Roleid as a repeating field SELECT MIN (UserID) as UserID, Roleid from Tmptable GROUP by Roleid SELECT Roleid from Tmptable GROUP by Roleid (COUNT (*) > 1) SELECT DISTINCT * from tmptable

When we use the sybase database, we often use excel to read the content in excel and insert it into the sybase Database Table. During this process, ex When we use the sybase database, we often use excel to read the content in excel and insert it into the sybase Database Table. During this process, ex Abstract: when using the sybase database, we often use excel to read the content in excel and insert it into the sybase database table, in this process, there are often line breaks in excel (lin

additions and deletions to the view, and then we will introduce how to integrate the open source IM user system by establishing the views and adding additions and deletions to trigger the lesktop. First introduce the structure of the Users table in the Lesktop open-source IM database:If the user table for your site (if the name is myusertable) is only name,nickname:Then, you can create an extension table (if the name is Userextentim) to store additional information:Next, you just need to delete

Tags: sql StackOverflow de-weightproblemSuppose you have a table with a larger amount of data (for example, 300,000+ rows), where there are duplicate rows (other than the primary key, the other column data is the same), how do you quickly go heavy? My watch looks like this.MyTable-----------RowID int not null identity(1,1) primary key,Col1 varchar(20) not null,Col2 varchar(2048) not null,Col3 tinyint not nullEssence AnswerAssuming there are no null va

Abstract: when using the sybase database, we often use excel to read the content in excel and insert it into the sybase database table, in this process, there are often line breaks in excel (line breaks are not visible). After being imported to a table, there are often different errors caused by line breaks. So how can I quickly remove/x0a directly? First, how to collect/x0a, and then remove/x0a.1. The cabl

* to Zhuisuo ORDER by ID ASC) m ORDER BY m.id Desc This sentence is not can be run).A derived table is a virtual table to be externally referenced. the order by returns not a table but a cursor . So the only order by is limited. But why is it possible to use top plus order by? is because top can select a specified number from the cursor returned by the order by to generate a table and return. Another example of the top need to pay attention to the details 1. Using top to return random rows

columns are added to resolve.2, this kind of repetition problem usually requires to keep the first record in the duplicate record, the operation method is as followsSuppose there is a duplicate field name,address, which requires the result set to be unique for both fieldsSelect Identity (int,1,1) as Autoid, * into #Tmp from TableNameSelect min (autoid) as autoid into #Tmp2 from #Tmp Group by name,autoidSELECT * from #Tmp where autoid on (select Autoid from #tmp2)The last select is the result se

Remove userid group_concat (title) group_concat (oid) group_concat (statue) from the same field in SQL query) 1 warranty, warranty, tutorial sp111, sp234, sp134 1 0 1 Based on this statue attribute, if the content with the same title value is 1, it will be removed if it is reserved as 0. Userid group_concat (title) group_concat (oid) group_concat (statue) 1 warranty, tutorial sp111, sp234, sp134 1 Re

insert (len/1000+1) times " "groups=divideintogroups (alltuples) Count=0 forGrouptuplesinchgroups:affectrows=Db.executemany (Insertsql, Grouptuples)ifAffectrows:count+=affectrows db.commit () needinsertnum=Len (alltuples) ispassedmsg= ('OK' ifNeedinsertnum==countElse 'SOME ERROR') Printandlog ("need insert%d records, and actual%d.%s"% (Needinsertnum, Count, ispassedmsg))The calling method is as follows:Insertsql = "INSERT into student (name, age) value (%s,%s)"Alltuples = [("Zhang", +), ("Qian"

Turn from Hibiscus bloghttp://blog.sina.com.cn/liurongxiu1211 SQL to remove duplicate statements(2012-06-15 15:00:01)SQL single table/multi-table query removes duplicate recordsSingle table DistinctMulti-table GROUP byGroup by must be placed before order by and limit, or it will be an error**************************************************************************

([Idx_noncls_include_ Exceptorderid])' shenzhen ' GO As you know, nonclustered index columns do not need to contain columns that create a clustered index, so what exactly is the fact? Conclusion: In fact, there is no need for any nonclustered index column to contain the column that created the clustered index, because the column that creates the clustered index is part of the nonclustered Index collection column, which means that the nonclustered index collection column contains the clustered

1. Preface 2. Delete through SSMs 3. Delete by SQL statement 3.1 Deleting a single row of data 3.2 Delete all row data 3.3 Deleting tables and databases 1. PrefaceAdditions and deletions are the operation of the data, where "delete" the corresponding SQL statement is "delete", that is, "delete" meaning.This article mainly introduces the deletion of data, respectively, using Ssms/

sp_addarticle @publication = ' publication ', @article = N ' article ', @source_ Object = N ' article ', @source_owner = n ' dbo ', @schema_option = 0x0000000008037cdfgo--Joins an unpublished column (adds one more column to the published table, typically does not) Exec sp_ Articlecolumn @publication = ' publication ', @article = n ' article ', @column = n ' column ', @operation = n ' Add ' go--for row filtering (for filtering advertisement) Exec sp_articlefilter @publication = N ' publication '

> carriage return Select *, replace (detail, char (13), ' 2> linefeed Select *, replace (detail, char (10), ' 3> enter a line break Select *, replace (detail, char (13) + char (10), ' 4> Replace the carriage return with the line break Update loginfoSet Detail = Replace (detail, char (13) + char (10), ' Note: In the DOS \ win series, the carriage return + linefeed char (13) + char (10) will appear) Line breaks in Unix/Linux For conversion, you only need to

){Console.WriteLine ("{0} Exception caught.", ex);}Third, modify the dataString Categoryname=textbox2.text;String Categorydescription=textbox3.text;String myconn= "Server=127.0.0.1;uid=user;pwd=123456;database=northwind; Trusted_connection=no ";SqlConnection myconnection=new SqlConnection (myconn);String myupdate= "Update Categories set categoryname= '" +categoryname+ "', description= '" +categorydescription+ "' where Categoryid= "+textbox1.text;SqlCommand mycommand=new SqlCommand (myupdate,myco

be unique for both fieldsSelect Identity(int,1,1) asAutoid,* into#Tmp fromTableNameSelect min(autoid) asAutoid into#Tmp2 from#TmpGroup byname,autoidSelect * from#TmpwhereAutoidinch(SelectAutoid from#tmp2)The last select is the result set that name,address not duplicate (but one more autoid field, which can be written in the SELECT clause without this column in the actual write)FourDuplicate querySelect * from where inch (Selectfromgroupby hascount> 1 )3. Find redundant duplicate records (m