sql server aggregate functions

' Zhejiang Province ' end) as Zhejiang from student group by sexIt's close to our request, now just add a few more fields.7.select Sex, Count (case province when ' Guangdong ' then ' Guangdong Province ' end ' as Guangdong Province, Count (case province when ' Jiangxi ' then ' Jiangxi ' end) as Jiangxi, Count (case province when ' Zhejiang ' then ' Zhejiang Province ' end) as Zhejiang from student group by sexSummary: Of course there are many ways to achieve a number of sub-query stitching up i

groupedSuch as:-The total number of girls and boys receivedSelect Sex,count (*) from Student GROUP by sexOrder of Query statements:Select from where the group by has an order byNote: Where is the filter for the source data. It can only use columns that are referred to in the table following the fromAn aggregate function cannot be used after a where condition, and an error will be made if usedHavingIf you are filtering the result set after grouping, t

Label:We all know that when a case is applied in SQL, the information in the database is converted For example, select (Case sex if 0 then ' men ' else ' end) as sex from Studentinfo So what does it do in the aggregate function? SELECTSex fromStudentSELECTSexCOUNT(*) asNum fromStudentGROUP bySexSELECTSex,province,COUNT(*) asNum fromStudentGROUP bysex,provinceSELECTSex,province,COUNT(province) asNum fro

Aggregate functions count, max, min, avg, sum...Select count (*) from T_EmployeeSelect Max (FSalary) from T_EmployeeSort ASC ascending DESC descendingSelect * from T_Employee order by FageSort by age in descending order. Sort by salary in ascending order if the age is the sameSelect * from T_Employee order by FAge DESC, FSalary ASCOrder by must be placed after the where clauseWildcard filterUse like for wil

Aggregate functions count, max, min, avg, sum... Select count (*) from T_Employee Select Max (FSalary) from T_Employee Sort ASC ascending DESC descendingSelect * from T_Employee order by Fage Sort by age in descending order. Sort by salary in ascending order if the age is the sameSelect * from T_Employee order by FAge DESC, FSalary ASC Order by must be placed after the where clause Wildcard FilterUse like

Aggregate functions count, max, min, avg, sum...Select count (*) from T_EmployeeSelect Max (FSalary) from T_EmployeeSort ASC ascending DESC descendingSelect * from T_Employee order by FageSort by age in descending order. Sort by salary in ascending order if the age is the sameSelect * from T_Employee order by FAge DESC, FSalary ASCOrder by must be placed after the where clauseWildcard FilterUse like for wil

SC GROUP by SNO have Count (*) >=2 and min (grade) >=60--8, query the number of students who took 2 courses, the course number and results, the results of the query in descending order by grade.Select Sno,cno,grade from SC where cno=2 order by grade DESC--9, professional names and numbers of professionals with less than 2 professional enquiries.Select Sdept,count (*) as number from student group by Sdept have COUNT (sdept) --10, query the name of female students, professional names, results by

Select Name,salespersonid from Sales.Store where Name between ' G ' and ' J ' and SalesPersonID > 283 ORDER by Sal Espersonid,name DESC/ASCThe use of the between of this statement is still very innovative, this between is the beginning of G and J between the beginning, do not know what the Chinese characters will be?Group BY, often with the min max sum avg, with the as name alias. The group by Mate aggregation function is commonly used.When Count (column) is NULL, the column is not count to .

1. What is an aggregated index (clustered index)/What is a non-aggregated index (nonclustered)?The index can be understood as a special kind of directory. Microsoft's SQL Server provides two types of indexes: Clustered indexes (clustered index, also called clustered indexes, clustered indexes), and nonclustered indexes (nonclustered index, also called nonclustered indexes, non-clustered indexes). Let's take

After one weeks, I finally began to write a third article. Get Up!Aggregation functions:The aggregate functions provided in SQL can be used to count, sum, find the most value, and so on.Classification:–count: Number of statistics rows–sum: Gets the aggregate value of a single column–avg: Calculating the average of a co

Document directory SQL group by syntax SQL having syntax Ii. Aggregate functions and group queries 1. Aggregate functions Common Aggregate fu