list of aggregate functions in sql

(including duplicate data) in the list/*Create Table with 7 records-3 is duplicate records*/CREATE TABLEDeleteduplicatetest (Col1INT, Col2INT )INSERT intodeleteduplicatetestSELECT 1 , 1 UNION All SELECT 1 , 1 --Duplicate UNION All SELECT 1 , 1 --Duplicate UNION All SELECT 1 , 2 UNION All SELECT 1 , 2 --Duplicat

, Ymd, YDM, MyD, and Dym. ... This setting is used only in the interpretation when converting a string to a date value. It does not affect the display of date values. ... Set DateFormat settings are set at execution or runtime, not at parse time. ... Set DateFormat overrides the implicit date format setting for set LANGUAGE. Here is an example:-Set date format to year, day, month. SET DateFormat YDM; GO DECLARE @datevar DATETIME; SET @datevar = ' 1998/31/12 '; SELECT @datevar as Datevar; GO-Set

Tags: calls to data stored procedures NBSP;NBSP;NBSP;OTHERSNBSP;NBSP;NBSP;HIGHLIGHTNBSP;NBSP;NBSP;ETC Results Assignment log usage --pl/sql Basic Knowledge Learning--one, PL/SQL statement block, basic syntax format declare--variable declaration list Info varchar (25); --Variable declaration stu_unm integer: = 15; BEGIN--statement block info: = ' Soulsjie '; -

warehouse ', ' A-1 'UNION ALLSelect ' B ', ' B warehouse ', NULLFrom the above data can be seen, a Zicang for A-1 and A-2 Warehouse, and A-1-1 for the A-1 of the sub-warehouse, B is a separate warehouse, and a warehouse lateral.Below, we use the with AS function to detect all the sub-positions below the position a:With W_storage_depository as(Select Did,dname,pid from storage_depository where did= ' A 'UNION ALLSelect A.did,a.dname,a.pid from Storage_depository a,w_storage_depository B where A.

' A-2 ', ' A-2 warehouse ', ' A 'UNION ALLSelect ' A-1-1 ', ' a-1-1 warehouse ', ' A-1 'UNION ALLSelect ' B ', ' B warehouse ', NULLFrom the above data can be seen, a Zicang for A-1 and A-2 Warehouse, and A-1-1 for the A-1 of the sub-warehouse, B is a separate warehouse, and a warehouse lateral.Below, we use the with AS function to detect all the sub-positions below the position a:With W_storage_depository as(Select Did,dname,pid from storage_depository where did= ' A 'UNION ALLSelect A.did,a.d

determine whether the layaway value is used to purchase the order when the order exceeds $200.SELECT Orderamt,CaseWhen Orderamt When Orderamt When Orderamt CaseWhen layaway = ' N 'Then ' no layaway $200 orders 'ELSE ' $200 order with Layway ' endOtherCaseWhen layaway = ' N 'Then ' no layaway $300 orders 'ELSE ' $300 order with Layway ' endEnd as Orderamt_categoryFrom MyOrder;Listing 7: Nested case statementsThe code in Listing 7 is similar to the code in Listing 6. The only difference is that I

Tags: style color using IO strong AR data CTI codeIn SQL Server, users can not only use standard built-in functions, but also use their own defined functions to implement some special functions. Can be created using the Create FUNCTION statement. It is important to note that the function name must be unique in the data

null result Select SUBSTRING (' ABCDE ', 0,8) returns the result as ABCDE, noting that there are no spaces behind it. (2) if the index of start starts at 1 (0 or negative ), the return length is equal to 1, the intercept length is the absolute value (start-1), and if the difference is negative, the return is empty . Draw a diagram to understand this situation (e.g. substring (' ABCDE ', 0,2) returns a): Coordinates: 0 1 2 3 4 5Content: null a b c d EIntercept: intercept from here to end For ex

Label:  Pl-sql storage functions and stored procedures ORACLE provides the ability to store PL/SQL programs in a database and to execute them wherever they are. This is called a stored procedure or function.Procedures and functions are collectively referred to as PL/SQL su

: can go directly or select cast (' 2004-09-08 ' as datetime) valueO:select to_date (' 2004-01-05 22:09:38 ', ' yyyy-mm-dd hh24-mi-ss ') Vaule from DUAL;43. Find the difference between a part of two dates (e.g. seconds)S:select DateDiff (Ss,getdate (), GETDATE () +12.3) valueO: Subtract directly from two dates (e.g. d1-d2=12.3)SELECT (D1-D2) *24*60*60 vaule from DUAL;44. Date of novelty based on difference (e.g. minutes)S:select DateAdd (Mi,8,getdate ()) valueO:select sysdate+8/60/24 vaule from

value in the group.Null values are ignored. OVER clause.">You can follow the over clause later. OVER clause.">The Checksum_agg is used to detect changes in the table. If a value in the expression list changes, the checksum of the list is usually changed. But in rare cases, the checksum remains the same. In many cases, this function should be used to detect whether the data in the table has changed or

modify information, and DML uses statements such as INSERT, select, Update, and delete to manipulate the data contained by database objects. (1). Create a table with an existing table Syntax: CREATE TABLE Select Column_names from eg 1), CREATE TABLE tb_dept as SELECT * from dept; 2), CREATE table tb_dept as select A.deptno, A.dname from dept A; 3), CREATE TABLE tb_dept as SELECT * FROM dept a where a.deptno=10; (2), select a row without duplicates, use the DISTINCT keyword eg, select distinc

number, name fromStaff A return - End - Go the Select * fromMingdan () - - --EG4: Custom function generates default values: - Go + Create functionDefault_num () - returns varchar(7) + begin A Declare @ number varchar(7) at Declare @id int - Select Top 1 @ number=Number fromTestorder byNumberdesc - if @ @rowcount=0 - Set @ number='tcp_001' - Else - begin in Set @i

When you list all the field names in a table, you use one of these SQL functions: object_id Here I list the function and usage so that you can understand: OBJECT_ID: Returns the database object identification number. Grammar OBJECT_ID (' object ') Parameters ' Object ' The object to use. The data type of object

include MDY, dmy, Ymd, YDM, MyD, and Dym.... This setting is used only in the interpretation when converting a string to a date value. It does not affect the display of date values.... Set DateFormat settings are set at execution or runtime, not at parse time.... Set DateFormat overrides the implicit date format setting for set LANGUAGE.Here is an example:--Set date format to year, day, month.SET DateFormat YDM;GODECLARE @datevar DATETIME;SET @datevar = ' 1998/31/12 ';SELECT @datevar as Datevar

: INSERT into Tb_stu (ID, Birthday) VALUES (1, to_date (' 20111130 ', ' YYYYMMDD '));6, clear screen: clear screens;7. Two single quotes in Oracle represent a single quotation markeg, update tb_stu set pwd= ' 1 ' 2 ' where id=1;8. Oracle MatchEg, select * from Tb_stu where pwd like ' A% '--matches multipleSELECT * from Tb_stu where pwd like ' a_ '--matches a9, drop table tb_dept purge; --Permanently deleteddrop table tb_dept; --Put the table in the Recycle Bin, and not completely delete the tabl

Label:Date-time functions　　1. Get the current date getdate The GETDATE () function returns the date and time of the computer on which the current SQL Server servers are located, in the format of the datetime data type. Its syntax format is GETDATE (). The return value is rounded to the nearest fractional fraction of the second, with a precision of. 333 seconds the database 17 offset is not included. Example

have a data type of char,varchar2,number,date. All grouping functions ignore null values. You can use NVL,NVL2, or the COALESCE function instead of a null value when you use GROUP BY, the Oralce server implicitly sorts the result set in ascending order. You can use order by to change the sorting result. You can use the NVL function to force a grouping function to contain null values, such as: Select AVG (NVL (comm,0)) from EMP;　　The syntax of the GRO

.... Set DateFormat settings are set at execution or runtime, not at parse time.... Set DateFormat overrides the implicit date format setting for set LANGUAGE.Here is an example:--Set Date format to year, day, month.SetDateFormat YDM;GoDeclare @datevar Datetime;Set @datevar = '1998/31/12';Select @datevar asDatevar;Go--Set Date format to year, month, day.SetDateFormat Ymd;GoDeclare @datevar Datetime;Set @datevar = '1998/12/31';Select @datevar asDatevar;Go(4)

affect the display of date values.... Set DateFormat settings are set at execution or runtime, not at parse time.... Set DateFormat overrides the implicit date format setting for set LANGUAGE.Here is an example:--Set date format to year, day, month.SET DateFormat YDM;GODECLARE @datevar DATETIME;SET @datevar = ' 1998/31/12 ';SELECT @datevar as Datevar;GO--Set date format to year, month, day.SET DateFormat Ymd;GODECLARE @datevar DATETIME;SET @datevar = ' 1998/12/31 ';SELECT @datevar as Datevar;GO