sql--aggregate function (Aggregate functions): Avg,count,first,last,max,min,sumavg () functionDefinition and UsageThe AVG function returns the average of a numeric column. NULL values are not included in the calculation.SQL AVG () syntaxSELECT AVG (column_name) from table_nameSQL AVG () instanceWe have the following "O
SQL has many built-in functions that can be used for counting and computation.Syntax of the functionThe syntax for the built-in SQL function is:SELECT function (column) from tableTypes of functionsIn SQL, there are several kinds of basic function types and
Added support for CLR in SQL Server 2005, which allows us to write functions, stored procedures, triggers, and other objects for SQL Server in C # and VB. NET languages. There is not much to say about how to create these objects. There are many searches on the Internet. Here we will talk about some noteworthy issues when creating
Tags: style blog http io ar color OS sp strongOriginal: "T-SQL Series" Common functions-aggregate functionsAggregation functionsAverage AVG, standard deviation Stdev, variance var, max Max, Min min, total sum, count of times, max-min, coefficient of variation stdev/avg*100What is statisticsStatistics is the process of inferring the overall characteristics through
Label:An aggregate function evaluates a set of values and returns a single value. In addition to the count (number of statistics) function, the other aggregate functions ignore null values (NULL) in the formula. All aggregate functions are deterministic
DistinctCount--column ProductModelID number of rows not duplicated, non-null valueFrom Production.Product--Note: Most of the aggregate functions support the "DISTINCT" keyword, so you can specify that the aggregate function executes only in data that is not duplicated in the specified group. For more information, refer to the
UNION All SELECT 1 , 'b' , Ten UNION All SELECT 2 , 'b' , 6 UNION All SELECT 3 , 'b' , Ten UNION All SELECT 4 , 'b' , 6 UNION All SELECT 5 , 'b' , 8--SELECT *--From @t1SELECTName as 'Shooting Hand' , AVG(score) as 'Average' , STDEV(score) as 'Standard dev
Tags: style blog http color io using AR data divSELECT R.industry_1,r.industry_2,r.agent_id,r.agent_name,COUNT (DISTINCT r.customer_name_a) total data,COUNT (DISTINCT case is r.ifhs= ' Y ' then r.customer_name_a END) amount of customs data,COUNT (DISTINCT case is r.ifgjh= ' Y ' then r.customer_name_a END) Canton Fair Data volume,COUNT (DISTINCT case when r.zlly like '% a class-% ' then R.customer_name_a END) old customer data volumeFrom Rep_com_allinfo R WHERE r.outbound= ' 10000115 'GROUP by R.
Tags: technology sharing parameters repeating expression repeating item variance 12c COM T-SQLAn aggregate function evaluates a set of values and returns a single value. In addition to the count (number of statistics) function, the other aggregate functions ignore null values (NULL) in the formula. All aggregate
SQL Aggregate functions and sorting methods
Aggregate functions count, max, min, avg, sum...Select count (*) from T_EmployeeSelect Max (FSalary) from T_Employee
Sort ASC ascending DESC descendingSelect * from T_Employee order by Fage
Sort by age in descending order. Sort by
Aggregation functions:The aggregate functions provided in SQL can be used to count, sum, find the most value, and so on.Classification:–count: Count rows –sum: Gets the aggregate value of a single column –avg: Calculate the average of a column – max: Calculate the maximum value of a column –min: Calculate the minimum v
When we write more complex SQL statements, we often encounter the need to put sum () into a where, as a conditional query, it turns out that this is not possible, execution will be reported "do not allow the use of grouping function" exception.So how to fix it, using the HAVING keywordExample:Select SUM (amount)From tableGROUP BY ClientIdHaving sum (amount) >100Special attention:1. Having to be behind group by (isn't that nonsense?)2, group by can onl
when generating DLLs, select the. NET Framework 3.5Step two: Enable database-to-CLR support configurationEXEC sp_configure ' clr enabled ', 1RECONFIGURE with OverridegoStep three: Load CLR assemblies and create custom functionsUse Test --Select database Create ASSEMBLY sql_aggregate from ' E:\WorkSpace\LetMeTry\WindowsFormsApplication2\ Sqlcustomfunction\bin\debug\sqlcustomfunction.dll ' Fourth Step: TestUse test--Creating test data CREATE Table TB (ID int,name varchar) INSERT into TB S
' 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
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
The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion;
products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the
content of the page makes you feel confusing, please write us an email, we will handle the problem
within 5 days after receiving your email.
If you find any instances of plagiarism from the community, please send an email to:
and provide relevant evidence. A staff member will contact you within 5 working days.