complex sql queries examples pdf

This article from: http://www.cnblogs.com/bluedoctor/archive/2011/08/10/2133983.html In general, our ORM framework usesSingle TableOrViewMap to oneEntity classSometimes stored procedures are mapped to object classes. If you do not want to write the stored procedures, how can these complex SQL queries be mapped to object classes? In fact, whether it is a si

empty table to hold the consecutive dates. You can then insert some data into the table. 1 declare @i int; 2 set @i=0; 3 while @i You can see the table insert and 1 to 400 ordered numbers: Then we can construct the continuous date, the addition of the date has already learned DATEADD (), if you want to study together, you can look at the previous notes: SQL Server Learning Note 1:http://www.cnblogs.com/liupeng61624/p/4354983.html

request is received. The query layer parses the SQL and produces an optimized execution plan by the executor, which is then referred to the execution engine to the storage layer for querying and calculation.If you need to use fireworks engine calculations, the query layer will further convert the execution plan into a distributed execution plan and submit it to the fireworks Cluster as a distributed task after the execution plan is obtained. The remo

Sql The Selectquerybuilder class allows you to create complex SQL statements and commands in your code. It also helps to avoid SQL injection attacks. 　　 introduceAdmit, and we've all done it, and think the following way is the best and the only way. Is that we build a lot of strings that contain all the WHERE clauses a

SQL queries complex data and displays statements SQL queries complex data and displays statements SQL queries

age of the students who have enrolled in course number 3rdSelect Cno,avg (grade) as AvggradeFrom SCGroup by cno//average results for each course studentSelect Course.cno ' Course Number ', COUNT (sc.sno) ' number 'From COURSE,SCwhere Course.cno=sc.cnoGROUP BY COURSE.CNO have Count (Sc.sno) >3 ORDER by Count (Sc.sno) desc,course.cno asc//? The number of students enrolled in each course is counted (more than 3 people). Requires the output of the course number and the number of electives, and the

setEnd Property ''' ''' Field Value''' Public property filevalue () as stringGetReturn m_filevalueEnd getSet (byval value as string)M_filevalue = ValueEnd setEnd Property End Class 'condition Next, there was another problem. I wanted to write SQL statement queries as a stored procedure, which was a headache because of the single quotation marks and spaces. Here I will share the final solution. Alter proced

The Selectquerybuilder class allows you to create complex SQL statements and commands in your code. It also helps to avoid SQL injection attacks. Introduced Admit, and we've all done it, and think the following way is the best and the only way. Is that we build a lot of strings that contain all the WHERE clauses and then commit them to the database to execute i

protocol, and the SQL is forwarded to the query layer for processing when the query request is received. The query layer parses the SQL and produces an optimized execution plan by the executor, which is then referred to the execution engine to the storage layer for querying and calculation.If you need to use fireworks engine calculations, the query layer will further convert the execution plan into a distr

minscopeFrom Test T,(Select A.type, max (a.scope) maxscope, Min (a.scope) minscopeFrom TEST AGroup by A.type) dwhere T.type = D.type--min ()/max () over (partition by ...)Select T.*,NVL (Max (t.scope) over (partition by T.type), 0)-T.scope maxscope,T.SCOPE-NVL (min (t.scope) over (partition by T.type), 0) MinscopeFrom Test T--lead ()/lag () over (partition by ...)Select T.*,lead (t.scope,1,0) over (partition by T.type ORDER by T.scope) a--the same group after oneFrom Test TSelect T.*,lag (t.sco

Label:14th: Using subqueries to define indeterminate data1, sub-query and select in combination withSelect Colum from table where column, where columnb= (select Colum_name from ...);2, sub-query and inset combined useInsert table1 Select Column1 from table2 where cloumn2> (select ...);Insert a few items in table two that meet the criteria into table 1, note: number of items inserted = number of Table13, sub-query and update use together4, sub-query and delete in combination with15th Chapter: Com

Examples of non-cyclic recursive queries in the SQL Server tree table, tree Recursion Many people may want to query the content associated with the entire tree-like table through recursive loops... in fact, Microsoft can use other syntaxes in SQL2005 or later versions. The following is an example. -- Query the parent node with tree as (SELECT * FROM Areas WHERE i

District, Peking City, China This code can be encapsulated as a stored procedure based on the above -----stored procedure, recursively gets the tree region table string if exists (select * from sysobjects where name= ' sp_getareastr ') drop proc sp_getareastrgo --exec sp_helptext ' sp_getareastr ' --go exec sp_getareastr go Query result: Lingbi County, Suzhou, Anhui Province, China Table structure used: Partial data: The above is a small set to introduce the