I need to select multiple columns but only have 2 of them which are distinct. For instance if i have
userid lastname firstname city country time
1 jones tom lon gb 2:25
2 wall paul la usa 2:30
1 jones tom lon gb 2:50
3 smith jane ny usa 2:55
what i would want to do is select all the columns but avoid duplicate lastname-firstname combination rows. The problem is if i use a group by i have to include all the columns and because time is different i will get tom jones twice. a way of getting round this so i can select all the columns but only 1 row of tom jones.
I had to create a new column in a particular table now i want to insert the values in that column though the other columns are already populated I entered the command (insert into Product(STANDARD_PRICE) values(895.99) when i hit return it says cannot enter null value into (SYSTEM .PRODUCT. PRODUCT_ID) product_id is the PK which is the first column STANDARD_PRICE is the last column in my table...how do i enter the values into that column without receiving this error or having to effect the other columns?
I need to write a query in plsql to select records for first 3 distinct values of a single column (below example, ID )and all the rows for next 3 distinct values of the column and so on till the end of count of distinct values of a column.
eg: ID name age 1 abc 10 1 def 20 2 ghi 10 2 jkl 20 2 mno 60 3 pqr 10 4 rst 10 4 tuv 10 5 vwx 10 6 xyz 10 6 hij 10 7 lmn 10 . . . so on... (till some count) Result should be Query 1 should result ---> ID name age 1 abc 10 1 def 20 2 ghi 10 2 jkl 20 2 mno 60 3 pqr 10
query 2 should result --> 4 rst 10 4 tuv 10 5 vwx 10 6 xyz 10 6 hij 10
query 3 should result --> 7 lmn 10 . . 9 .. .. so on..
I have a table with, for example, three columns: A, B,C.
I execute on this table only one select: CODESELECT * FROM TABLE WHERE A = :1 AND B=:2
Column A has a lot of distinct values (numbers), but B can have only two values: 'Y' or 'N' (cardinality about 50%/50%). It is worth to create index on two columns: A, B? Does query using index on A column will be much slower than using index on A, B?
I have in my database (OLTP-System) a table with about 6000000 records and a zise of about 2GB.
the way to create multi_column indexes on the table?
What are the rule to define the best-position of a column in an index?
index_1(col_1,Col_2,col_3) and not [ (col_1,Col_3,col_2) or (col_2,Col_3,col_1) or (col_2,Col_1,col_3) or (col_3,Col_2,col_1) or (col_3,Col_1,col_2) ] ?
explain slow performance of multicolumn indexes on oracle 11g R2 observed in the following scenario? A multi-column index (b-tree index) not partitioned, not unique, not reversed with 3 columns.
A series of queries are run using all 3 columns. The performance hit comes when the first order column values changes. So, maybe after 10 select queries the value changes. The 2nd and 3rd order columns are changing throughout the series of select calls, but no performance bottleneck it hit then.
I need to take the distinct values from VARRAY.. I have wrote following simple example. But it does not work. how to get the distinct value from VARRAY.
declare type t is varray(10) of varchar2(10); t1 t; type r is table of varchar2(10) index by binary_integer; r1 r; begin t1 := t('A','B','A','B','A','B','C'); select distinct * into r1 from table(select * from t1); END;
I have following query which gives currency code from two different tables. I would like to get the distinct count of currency codes from these two different columns.
SELECT eb.person_seq_id, eb.bonus_amount, eb.currency_cd, ed.currency_cd_host FROM fr_emp_bonuses eb, fr_emp_details ed, fr_periods p WHERE eb.person_seq_id = ed.person_seq_id AND ed.period_seq_id = eb.period_seq_id AND ed.period_seq_id = p.period_seq_id AND p.period_status = 'CURRENT' AND eb.bonus_amount >= 0 AND eb.person_seq_id = 3525125;
select field1,field2,field3 from Table1 union select field1,field2,field3 from table2
In the query from table2 i am getting duplicate rows, HOW can i retrieve only distinct rows...Using distinct keyword did not work...if i have to post create and insert statements for this one...
I have got the following error while executing below Query.
ORA-01791 'Not a SELECTed expression'
select distinct sgbstdn_levl_code from sgbstdn,spriden where spriden_pidm = sgbstdn_pidm and spriden_id = '200076543' order by sgbstdn_term_code_eff desc;
The above Query is not working with Distinct & Order By clause are present and by joining two tables. I need the distinct values of levels in Descending order of Terms.
The table creation and Data insertion script is attached with the message.Basically I want to sort all the data based on the order by clause and then remove duplicates from the TSKID column and get distinct TSKIDs in the same order.I have below query to sort data:
SELECT * FROM piwingetworkitems_vd ORDER BY profilepriority, authdptpriority, returnpriority ASC, priority DESC, effdate, tskid
But when I add a DISTINCT to the query, it does some kind of random sort and doesn't return the data as per above ORDER BY query and ignoring the SORT order.
SELECT DISTINCT tskid FROM (SELECT * FROM piwingetworkitems_vd ORDER BY profilepriority, authdptpriority, returnpriority ASC, priority DESC, effdate, tskid)
Is there any way to select the DISTINCT taskids ordered as per requirements?
I've read so many different pages on this topic but I can't seem to get my query the way it needs to be. Here's the query:
select admitnbr, lastname||', '||firstname||' '||finitial, hphone, mobile, wphone, med_rec, dob from patients join schedule using (key_patien) join adtmirro using (key_patien) where appt_state = 'ON HOLD'
Because patients in my database can have multiple appointments "on hold" there are duplicates in the results. I only need 1 record per patient in order to forward this information into an automated dialer to contact that patient. I do NOT want to call the patient over and over again. Once will suffice. I'm trying to make a distinction on the column 'med_rec'. One row per 'med_rec' will be awesome but I can't find a way to create a distinct on that column.
select distinct c.process_id a.role_id,a.email_address,c.process_name from role a, notification_role b, process c where a.role_id=b.role_id and b.process_id = c.process_id
I have a collection of objects built in a PL/SQL program.
I want to keep only the distinct elements of this collection for the rest of the program.
I failed to find the correct way to do it
For instance (the actual object is far more complex containing object attributes itself), with the following types:
drop type t1b / drop type t1a / create or replace type t1a as object ( v1 integer, v2 integer ) / create or replace type t1b as table of t1a / I have the following variable:
v t1b := t1b(t1a(1,2),t1a(1,2));
And I want to get only one "t1a(1,2)" in my collection.
My first idea (actually the second one but it does not matter) was to use DISTINCT:
SQL> declare
2 v t1b := t1b(t1a(1,2),t1a(1,2)); 3 begin 4 select distinct t1a(v1,v2) bulk collect into v from table(v); 5 dbms_output.put_line(v.count); 6 end; 7 / declare * ERROR at line 1:
ORA-22950: cannot ORDER objects without MAP or ORDER method ORA-06512: at line 4
As I said the object is far more complex and builting a MAP function is quite tedious (but I will do it if there is no other way).
The next idea was to use multiset operators:
SQL> declare 2 v t1b := t1b(t1a(1,2),t1a(1,2)); 3 begin 4 select v multiset intersect distinct v into v from dual; 5 dbms_output.put_line(v.count); 6 end; 7 / 1
PL/SQL procedure successfully completed.
This works well but I suspect this is not the correct way and there is one to do it in PL/SQL but currently failed to find it.
