SQL & PL/SQL :: Why Is It Necessary To Precede Group By Before Order By
Feb 10, 2013
Why is it necessary to precede group by before order by and not vice versa in a sql query? as the foll code gives an error select name from student order by age group by name;
select to_char(order_date,'mon-yyyy') "months", sum(nob) "number of bags" from p_in where order_date between '1-apr-11 and '31-mar-12' group by to_char(order_date,'mon-yyyy')
the above query returns me a resultset which gives me number of bags sold in every month, but it does not sort the month in their chronological order. i want to sort my resultset in ascending order of month s.,means jan-feb-march-apr-may ams so on...QUOTE
I have a table name as angdata77 having attributes like asigno..i want to retrieve data from angdata77 by using both group by & order by clauses.. for total count..am using the query as
select asigno,count(*) from angdata77 group by asigno order by asigno;
Is there any other query for retrieving the data from angdata77
Name Null Type --------------------------- -------- ------------- RPTNO NOT NULL NUMBER RPTDATE NOT NULL DATE RPTD_BY NOT NULL VARCHAR2(25) PRODUCT_ID NOT NULL NUMBER
describe rptbody
Name Null Type ------------- -------- ------------- RPTNO NOT NULL NUMBER LINENO NOT NULL NUMBER COMMENTS VARCHAR2(240) UPD_DATE DATE
The fact is that we store some header in RPTHEAD and store real data in RPTBODY, the question is that if I use below SQL to query all data for a 'PRODUCT_ID'.
SELECT t0.LINENO, t0.COMMENTS, t0.RPTNO, t0.UPD_DATE FROM RPTBODY t0 , RPTHEAD rpthead WHERE ( t0.RPTNO = rpthead.RPTNO AND t0.UPD_DATE>=to_date('1970/01/01 00:00:00','YYYY/MM/DD hh24:mi:ss') AND rpthead.PRODUCT_ID IN ('4647') )
I do not want to have 'ORDER by' clause since data set is too large, the sorting takes long time, is there any way to get the result rows in the order sorted by RPTNO? We have the index for RPTNO on RPTBODY.
I'm trying to group sets of data based on time separations between records and then count how many records are in each group.
In the example below, I want to return the count for each group of data, so Group 1=5, Group 2=5 and Group 3=5
SELECT AREA_ID AS "AREA ID", LOC_ID AS "LOCATION ID", TEST_DATE AS "DATE", TEST_TIME AS "TIME" FROM MON_TEST_MASTER WHERE AREA_ID =89 AND LOC_ID ='3015' AND TEST_DATE ='10/19/1994';
[code]....
Group 1 = 8:00:22 to 8:41:22
Group 2 = 11:35:47 to 11:35:47
Group 3 = 15:13:46 to 15:13:46
Keep in mind the times will always change, and sometime go over the one hour mark, but no group will have more then a one hour separation between records.
I read that rownum is applied after the selection is made and before "order by". So, in order to get the sum of salaries for all employees in all departments with a row number starting from 1, i wrote :
select ROWNUM,department_id,sum(salary) from employees group by department_id
If i remove rownum, it gives the correct output. Why can't rownum be used here ?
I'm using this code, and it performs fine, but I'm wondering if there is a more elegant way to do it--maybe with "ROLLBACK". Basically (as you can see) I need to get a normal count for each group but also for each group take a percentage of the total count (so all groups pct adds up to 100 (oh yeah, don't test for zero below, but just a test... )
select c.Event, c.code, count(1) as calls, total.total_count, count(1) / total.total_count * 100 as pct_of_total from table1 c
[Code]....
[Edit MC: add code tags, do it yourself next time]
I am having table without any primary key. In this table, only inserts and deletes are performed , no update operation.
Is it safe to use order by rowid on such a table ? Does by applying order rowid, is it possible to check order in which rows were inserted in this table ?
Select clause or Order by clause? First the columns specified in the select clause are fetched and then ordered or is it the vice -versa? In a query if a psuedo-column rownum is selected, then if we use order by on the rownum column, what happens?
What would be the output of the following query and why?Which part of the query is first executed, is it select clause or order by clause?
select empno,ename,rownum from emp order by rownum desc;
I rearranged the fields on a form, so I want the tab order to be different. I rearranged the fields in the object navigator to be in the order I want them to tab. I made sure the Previous Navigation Item and Next Navigation Item were set to null for all the fields.
Still it keeps the old tab order.
I also tried explicitly specifying the Previous Navigation Item and Next Navigation Item. Same thing, it kept the old tab order before I rearranged the fields. Previous Navigation Item and Next Navigation Item are both null.
There are no triggers on these fields. All fields are in the same block. I am using Oracle Form Builder version 9.
I have a column named "col1" with datatype "varchar2(10)" and row wise entries like "1,1A, 2,3...,10,2A,..." like. I want to order it like "1, 1A ,2,2A, 2B,3... 10...".I tried it with to_number() but it gives me
I have requirement to create an XML structure through stored procedure. I need to Order some of the columns in ascending order before I format them into the xml structure. I am pretty novice to creating an output into XML format, but attached is the query I came up with (without order by). This works perfect, but now the requirement is to order by - cls_cd, and within cls_cd, again order by - cat_cd. I am not able to do this.
insert into x values('A-1'); insert into x values('B-1'); insert into x values('B-2'); insert into x values('B-3'); insert into x values('1'); insert into x values('A-2'); insert into x values('2'); insert into x values('3'); insert into x values('A-4'); insert into x values('B-4'); insert into x values('C-4'); insert into x values('D-4');
I've got a TRANSACTION table with about 4, 681 transactions going on over the course of a given year (this is a project for my DB class). I'm trying to create a query that will give the base revenue for each month in that year; so far I've come up with the following:
SELECT DISTINCT CASE WHEN EXTRACT(MONTH FROM transaction_date) = 1 THEN 'JAN' || ' ' || EXTRACT(YEAR FROM transaction_date) WHEN EXTRACT(MONTH FROM transaction_date) = 2 THEN 'FEB' || ' ' || EXTRACT(YEAR FROM transaction_date) WHEN EXTRACT(MONTH FROM transaction_date) = 3 THEN 'MAR' || ' ' || EXTRACT(YEAR FROM transaction_date) WHEN EXTRACT(MONTH FROM transaction_date) = 4 THEN 'APR' || ' ' || EXTRACT(YEAR FROM transaction_date) [code]....
The query returns twelve months, but they're all jumbled up. I tried extracting the month in the ORDER BY subclause
ORDER BY EXTRACT(MONTH FROM TO_DATE(month, 'MM YYYY'));
But I got an ORA-01866: the datetime class is invalid. I'm using Oracle 10g xe (outdated, I know). get the months to show up in order?
I am using 11GR2 and looking to find out a way , where in I able to extract the data files name in such a manner , where it lists data file in order of mount points. say data1 first and then so on.. Snippet from my data files
like /db/ptmtrain/data1/system01.dbf/db/ptmtrain/data1/undotbs01.dbf/db/ptmtrain/data2/sysaux01.dbf/db/ptmtrain/data2/rbs03.dbf/db/ptmtrain/data2/rbs01.dbf/db/ptmtrain/data3/tools01.dbf/db/ptmtrain/data3/rbs02.dbf/db/ptmtrain/data23/sans01.dbf/db/ptmtrain/data24/users01.dbf/db/ptmtrain/data25/users02.dbf/db/ptmtrain/data26/users03.dbf
How I can see the order by employees,year wise and monthwise (month should start from january and so on..)
SELECT ENAME,TO_CHAR(HIREDATE,'yyyy') YEAR,TO_CHAR(HIREDATE,'Month') MONTH ,count(*) total FROM EMP GROUP BY TO_CHAR(HIREDATE,'yyyy') ,TO_CHAR(HIREDATE,'Month');
I have a varchar2 column which can hold numeric values, and also varchar2 values.
The following select returns only the records which have a number value in that column
select * from my_table order by decode( replace(translate(valoare,'1234567890.','00000000000'),'0',''), NULL, valoare, 0 ) != 0;
But how can i order that column, so that first are the numbers (also ordered), and then the varchar2 columns (so all the rows of that table are selected, both varchar2 values and numbers in that column)? Is it possible?
I have a requirement where I need to display a list of employees, performance rating and manager id. I want to display the employees first whose manager is as manager_id as input parameter. So lets say a manager logs in, he should see his reporters first and then the rest. How can I implement this in SQL? I am trying first clause with order by but not sure how to do that here.
I want to get value in EMP column with following statement: ------------- SELECT EMP FROM emp ORDER BY COMPANY (But 9999 is first), OFFICE (But 99999 is first). -------------
I have a query with order by clause, which takes 30 sec to execute with order by clause. And if i remove the order by clause it executes within 1 sec.
The column in the order by condition has index. but when i see Explain plan output. it doesn't show this index is being used. I tried to execute query with INDEX hint but still explain plan is not showing this index.
i have a table test on 4 different-different database, at the starting structure is same in all the database. and now i want to change the datatype of the primary key column named "testid" , then i add a temp column in test table (and it is added at the last in table).
i have copied the data of testid in temp column and renamed it as testid and i dropped the testid column , then the problem is that primary key column will comes at last and i want to make it like previous position so that there will not be any difference in all 4 database as in structure.
is it possible to changing column order as our desire without dropping the table?and i made all the script to changing the datatype of primary key column.