oracle sql analytic functions

Tags: src return inf same IMA body height img Share1. RANKThe--rank function returns a unique value that, when the same data is encountered, ranks the same as the last and next rank between the same data.Column:2, Dense_rank--Returns a unique value that, when the same data is encountered, ranks the same, encounters different data, does not empty the rank, but increments.Column:3, Row_number--return unique values, same data, rank different, increment, seeColumn:The role and difference of

) rangebetweenInterval'2' DayPreceding andInterval'2' Dayfollowing) Five_day_avg fromCust_orderwhereSale_price is not NULL andOrder_dtbetweenTo_date ('01-jul-2001','dd-mon-yyyy') andTo_date ('31-jul-2001','dd-mon-yyyy')--displays sales for the current month, one months, one months, and average sales for every 3 monthsSelect Month, First_value (sum(Tot_sales)) Over (Order by MonthRowsbetween 1Preceding and 1following) Prev_month,sum(tot_sales) Monthly_sales,last_value (sum(Tot_sales)) Over (

(Rank, Dense_rank, Row_number) ①row_number:12345The row_number function returns a unique value that, when the same data is encountered, is incremented sequentially in the order in which the records are recorded in the recordset. ②dense_rank:12223The Dense_rank function returns a unique value unless all the same data is ranked the same at the time when the same data is encountered. ③rank:12225The rank function returns a unique value, except that when the same data is encountered, all the same dat

analytic functions provide a much quicker way to check gaps. They enable you to still see the next line (lead) or the previous line (LAG) values while using full, set-oriented SQL processing. The following are the formats for these functions: {lead | LAG} (value_expression, offset, default) over ([PARTITION to exp

the same at the same time, and the rank between the last same record and the next record rank is vacated.Map instructions in turn:　　　　It can be seen that the data encountered by rownum, whether or not they are the same, are sorted in order; Dense_rank when the same data is encountered, the same data is ranked the same, but the corresponding ranking is vacated; rank has the same data when it encounters the same data and does not empty the corresponding rankings.The over () function cannot be use

Tags: ACL tween pre from GES. com Understanding First SeleThe literal meaning of First_value () and Last_value () is intuitive, taking the values of the records.Example: Query department The earliest occurrence of sales record date and recent sales record date Select dept_id , Sale_date , Goods_type , sale_cnt over byorder by sale_date) First_value throughorderbydesc ) Last_value from Criss_sales; Look at the results first_value () very intuitive, no more

Ratio_to_report--List Sales totals per month of the previous year, year-end sales, and monthly sales as a percentage of total annual sales--method ①:SelectAll_sales.*, - * round(Cust_sales/Region_sales,2)|| '%' Percent from (SelectO.CUST_NBR customer,o.region_id Region,sum(o.tot_sales) cust_sales,sum(sum(O.tot_sales)) Over(Partition byo.region_id) Region_sales fromorders_tmp owhereO. Year = 2001 Group byo.region_id, O.CUST_NBR) all_saleswhereAll_sales.cust_sales>All_sales.region_sales* 0.2;--m

I. Statistical aspects:Sum() Over([Partition by] [Order by])Sum() Over([Partition by] [Order by]RowsbetweenPreceding andfollowing)Sum() Over([Partition by] [Order by]RowsbetweenPreceding and CurrentRow)Sum() Over([Partition by] [Order by]RangebetweenInterval"' ' Day'Preceding andInterval"' ' Day'following) second, arrangement: Rank () Over([Partition by] [Order by] [Nulls First/last]) Dense_rank () Over([patition by] [Order by] [Nulls First/last]) row_number () Over([Partitionby] [Order by] [Nu

--Check the salary rankings of all teachers--rank (): Same row with equal values, followed by rank jumpsSelect Tname,sal,Rank () Over (order by Sal) as salary rankFrom teacher--dense_rank (): The same row with equal values, followed by successive rankingsSelect Tname,sal,Dense_rank () Over (order by Sal) as salary rankingFrom teacher--row_number: The returned rank is contiguous regardless of the value equalitySelect Tname,sal,deptno,Row_number () Over (order by Sal) as salary rankingFrom teacher

. No groupingExplain:Sequencing has continuity: Dense_rank () Over (Order by column), for example: 1, 2, 2, 3, 3, 3, 4Sort without continuity: rank () Over (Order by column), for example: 1, 2, 2, 4, 4, 4, 4, 8Query a subject for all student grades, from high to Low: note: The order by default is sorted in ascending order, and Desc is descending from high to lowDense_rank () Over (Order by column):Select Over (orderbydesc) Ranknum,s.studentid,s.score from S_score S where = ' A ';　　Rank () Over

Intersect operator returns only the public rows of two queries. The minus operator returns the rows that appear in the second query from the first query result. >select OrderNo from Order_master minus select OrderNo from Order_Detail; 　　　　 　　Join operator The join operator is used to combine multiple strings or data values into a single string >select (venname| | ' The address is ' | | venadd1| | ' ' | | venadd2| | ' ' | | VENADD3) address from Vendor_master where vencode= ' v001 '; --by using

as Wages from employ; The results of the query are as follows: ordinal name Department salary 1 Zhaohong Technical Department 2 John Marketing Department 4000 3 Wang Lan Technical Department 4000 4 Dick Marketing Department 5000 5 Li Bai Technical Department 5000 6 Harry Marketing Department (NULL) See the above row_number () over (). A lot o

SQL single-line functions in Oracle databases-character FunctionsThis learning is about character functions.Character FunctionsCharacter functions can also be divided into case-insensitive conversion functions and character processing functions.Case-sensitive conversion func

Oracle Database SQL single-row functions-date functionsPrefaceThe date functions of the Oracle database are very powerful and relatively large. I will sort it out for future reference.. Convenience for yourself and convenience for others!Common date functions1. Sysdate: curr

I. oracle basic SQL statements and functions, and oraclesql Functions I. Data Definition Language (ddl) Data definition language (ddl) is used to change the database structure, including creating, changing, and deleting database objects. The Data Definition Language commands used to manipulate the table structure inclu

PL/SQL single-line functions and group functionsA function is a program that has 0 or more parameters and has a return value. Oracle has built a series of functions in SQL, which can be called SQL or PL/

SQL single-row functions in Oracle databases-continued character FunctionsI practiced some character functions in the previous blog, and then I went to the next blog to read the relevant materials.The character function has not been practiced yet. This time, we mainly perform some supplementary exercises on some unused