Query regarding Oracle SQL select statement

Hi,
How does Oracle ensures a consistent snapshot with the select statement
without locking the table. My question is summarized with an example below:
1. At time T1, Oracle select statement is fired and is fetching the result.
2. At time T2, some DML operation is performed on the same table on which
the select was executed and a commit was fired.
3. At time T3, The Oracle select statement (Step 1) completes.
My question is whether the records of transaction at time T2 will be visible at time T3 or not?
If "not", then does it mean that Oracle retrieves the rows from the time of last commit.
I would also like to know if for the above mechanism, Oracle would make use of the rollback segemt to access the rows at a particular instant of time.
TIA
Regards,
Raj

This is called Read Consistency in the oracle. Its all about SCN before starting the transaction.
Lets say
1. T1 executs SELECT statement on EMP table.
2. T2 made an update on the EMP and commited.
But, T1 only still sees only old image of the data not the new one. This is called read consistency.
You will be having two images in the buffer, one is consistent and changed image.
When the T1 give SELECT statement it notes the SCN of the transaction. Read oracle document about read consistency.
SJH.

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Hi,
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Convert sql select statement to oracle

Hi All,
Can anyone help me converting this Sql select statement to oracle ....
-----------------------------------------Query--------------------------------------------------------------
select emp_master.emp_code ,
emp_master.dept_cd ,
attendance_master.daily_attn_code ,
attendance_master.linked_column ,
case when location.payroll_status <> 'N' and eDocsNetEmployeesLeave.StartDate < dateadd(mm, 1 , convert(smalldatetime, datename(yy ,location.next_pay_date) + '/'+ datename(mm ,location.next_pay_date)+ '/01'))
then
dateadd(mm, 1 , convert(smalldatetime, datename(yy ,location.next_pay_date) + '/'+ datename(mm ,location.next_pay_date)+ '/01'))
when eDocsNetEmployeesLeave.StartDate < convert(smalldatetime, datename(yy ,location.next_pay_date) + '/'+ datename(mm ,location.next_pay_date)+ '/01')
then convert(smalldatetime, datename(yy ,location.next_pay_date) + '/'+ datename(mm ,location.next_pay_date)+ '/01') else eDocsNetEmployeesLeaveDetails.StartDate
end ,
eDocsNetEmployeesLeaveDetails.NoOfDays,
case when eDocsNetEmployeesLeave.StartDate > location.next_pay_date
then convert(datetime , convert(varchar, dateadd(ss,-1, dateadd(mm, 1, convert(datetime , datename(yy,eDocsNetEmployeesLeave.StartDate)+ '/' + datename(mm,eDocsNetEmployeesLeave.StartDate)+ '/01') )),106) )
else
case when location.payroll_status <> 'N'
then dateadd(mm,1,location.next_pay_date)
else location.next_pay_date
end
end as PaymentDate               ,
isnull(grade_master.leave_type,'C') ,
eDocsNetEmployeesLeave.StartDate ,
eDocsNetEmployeesLeaveDetails.LeaveType
from eDocsNetEmployeesLeave ,
eDocsNetEmployeesLeaveDetails ,
eDocsNetLeaveTypes ,
emp_master ,
grade_master ,
attendance_master ,
location
where eDocsNetEmployeesLeaveDetails.RequestID     = eDocsNetEmployeesLeave.RequestID and
eDocsNetEmployeesLeave.EmployeeID = emp_master.emp_code and
eDocsNetEmployeesLeaveDetails.LeaveType = eDocsNetLeaveTypes.LeaveTypeID and
eDocsNetLeaveTypes.loc_cd = emp_master.loc_cd and
location.loc_cd = emp_master.loc_cd and
attendance_master.loc_cd = emp_master.loc_cd and
attendance_master.linked_column = eDocsNetLeaveTypes.LinkedAttendance and
grade_master.loc_cd = emp_master.loc_cd and
grade_master.grade_cd = emp_master.grade_cd and
eDocsNetEmployeesLeaveDetails.RequestID      = @RequestID
order by eDocsNetEmployeesLeaveDetails.StartDate
Thanks in Advance
Smiley

Seems like you want to convert a SQL statement from the ??? dialect to the Oracle dialect. *(It would be useful to indicate the non-ANSI standard SQL you are starting with.)
Part of the problem is that you use several date related functions. Some are unnecessary in Oracle and some need to translated into Oracle functions as found in the Functions section (chapter 5) of the SQL Reference manual at http://www.oracle.com/pls/db102/homepage
Note that columns and expressions of type 'date' in ORacle always contain all of "yyyy mm dd hh mi ss" and you need to format and trauncate as necessary.
Also note that '09-JAN-31' is NOT an Oracle date, but rather a character representation of a date which must be converted to/from a date expression. You will often need to use the to_date() and to_char() functions with a format mask as the second parameter. This is also descreibed in the first 2 chapters of the SQL Reference manual.

Jdev9i, JSP, Execute a Sql Select statement directly?

Hi,
I need the syntax to execute a Sql SELECT statement directly against Oracle database and access rows(returned by SELECT statemnet) in a JSP page or Servlet? Any sample code available for this.
Thanks.

Hi Ali,
I didn't work a lot with jsp ,but on this url some help .
http://otn.oracle.com/docs/products/oracle8i/doc_library/817_doc/java.817/a83726/basics7.htm#1014578

Exporting SQL Select statement to spreadsheet

Hi all, basic question that I couldn't find the answer to while googling and searching the Oracle documentation.
What is the code for exporting the result of a SQL Select statement to a spreadsheet such as Excel or Calc? In Oracle SQL Developer I tried saving the output as an XML file but it did not come out properly and I tried using EXPORT at the end of the statement but it gave an error message and I am not sure if this is the right command or what the syntax is. Thanks.

Here's an example of one way to create CSV files that most spreadsheet type applications are able to read...
As sys user:
CREATE OR REPLACE DIRECTORY TEST_DIR AS '\tmp\myfiles'
GRANT READ, WRITE ON DIRECTORY TEST_DIR TO myuser
/As myuser:
CREATE OR REPLACE PROCEDURE run_query(p_sql IN VARCHAR2
                                     ,p_dir IN VARCHAR2
                                     ,p_header_file IN VARCHAR2
                                     ,p_data_file IN VARCHAR2 := NULL) IS
v_finaltxt VARCHAR2(4000);
v_v_val     VARCHAR2(4000);
v_n_val     NUMBER;
v_d_val     DATE;
v_ret       NUMBER;
c           NUMBER;
d           NUMBER;
col_cnt     INTEGER;
f           BOOLEAN;
rec_tab     DBMS_SQL.DESC_TAB;
col_num     NUMBER;
v_fh        UTL_FILE.FILE_TYPE;
v_samefile BOOLEAN := (NVL(p_data_file,p_header_file) = p_header_file);
BEGIN
c := DBMS_SQL.OPEN_CURSOR;
DBMS_SQL.PARSE(c, p_sql, DBMS_SQL.NATIVE);
d := DBMS_SQL.EXECUTE(c);
DBMS_SQL.DESCRIBE_COLUMNS(c, col_cnt, rec_tab);
FOR j in 1..col_cnt
LOOP
    CASE rec_tab(j).col_type
      WHEN 1 THEN DBMS_SQL.DEFINE_COLUMN(c,j,v_v_val,2000);
      WHEN 2 THEN DBMS_SQL.DEFINE_COLUMN(c,j,v_n_val);
      WHEN 12 THEN DBMS_SQL.DEFINE_COLUMN(c,j,v_d_val);
    ELSE
      DBMS_SQL.DEFINE_COLUMN(c,j,v_v_val,2000);
    END CASE;
END LOOP;
-- This part outputs the HEADER
v_fh := UTL_FILE.FOPEN(upper(p_dir),p_header_file,'w',32767);
FOR j in 1..col_cnt
LOOP
    v_finaltxt := ltrim(v_finaltxt||','||lower(rec_tab(j).col_name),',');
END LOOP;
-- DBMS_OUTPUT.PUT_LINE(v_finaltxt);
UTL_FILE.PUT_LINE(v_fh, v_finaltxt);
IF NOT v_samefile THEN
    UTL_FILE.FCLOSE(v_fh);
END IF;
-- This part outputs the DATA
IF NOT v_samefile THEN
    v_fh := UTL_FILE.FOPEN(upper(p_dir),p_data_file,'w',32767);
END IF;
LOOP
    v_ret := DBMS_SQL.FETCH_ROWS(c);
    EXIT WHEN v_ret = 0;
    v_finaltxt := NULL;
    FOR j in 1..col_cnt
    LOOP
      CASE rec_tab(j).col_type
        WHEN 1 THEN DBMS_SQL.COLUMN_VALUE(c,j,v_v_val);
                    v_finaltxt := ltrim(v_finaltxt||',"'||v_v_val||'"',',');
        WHEN 2 THEN DBMS_SQL.COLUMN_VALUE(c,j,v_n_val);
                    v_finaltxt := ltrim(v_finaltxt||','||v_n_val,',');
        WHEN 12 THEN DBMS_SQL.COLUMN_VALUE(c,j,v_d_val);
                    v_finaltxt := ltrim(v_finaltxt||','||to_char(v_d_val,'DD/MM/YYYY HH24:MI:SS'),',');
      ELSE
        v_finaltxt := ltrim(v_finaltxt||',"'||v_v_val||'"',',');
      END CASE;
    END LOOP;
-- DBMS_OUTPUT.PUT_LINE(v_finaltxt);
    UTL_FILE.PUT_LINE(v_fh, v_finaltxt);
END LOOP;
UTL_FILE.FCLOSE(v_fh);
DBMS_SQL.CLOSE_CURSOR(c);
END;This allows for the header row and the data to be written to seperate files if required.
e.g.
SQL> exec run_query('select * from emp','TEST_DIR','output.txt');
PL/SQL procedure successfully completed.Output.txt file contains:
empno,ename,job,mgr,hiredate,sal,comm,deptno
7369,"SMITH","CLERK",7902,17/12/1980 00:00:00,800,,20
7499,"ALLEN","SALESMAN",7698,20/02/1981 00:00:00,1600,300,30
7521,"WARD","SALESMAN",7698,22/02/1981 00:00:00,1250,500,30
7566,"JONES","MANAGER",7839,02/04/1981 00:00:00,2975,,20
7654,"MARTIN","SALESMAN",7698,28/09/1981 00:00:00,1250,1400,30
7698,"BLAKE","MANAGER",7839,01/05/1981 00:00:00,2850,,30
7782,"CLARK","MANAGER",7839,09/06/1981 00:00:00,2450,,10
7788,"SCOTT","ANALYST",7566,19/04/1987 00:00:00,3000,,20
7839,"KING","PRESIDENT",,17/11/1981 00:00:00,5000,,10
7844,"TURNER","SALESMAN",7698,08/09/1981 00:00:00,1500,0,30
7876,"ADAMS","CLERK",7788,23/05/1987 00:00:00,1100,,20
7900,"JAMES","CLERK",7698,03/12/1981 00:00:00,950,,30
7902,"FORD","ANALYST",7566,03/12/1981 00:00:00,3000,,20
7934,"MILLER","CLERK",7782,23/01/1982 00:00:00,1300,,10The procedure allows for the header and data to go to seperate files if required. Just specifying the "header" filename will put the header and data in the one file.
Adapt to output different datatypes and styles are required.
There are other methods for specifically creating Excel workbooks with multiple sheets etc. and details can be found in the SQL and PL/SQL FAQ at the top of the forum:
{message:id=9360007}

Javascript and sql select statement

I am working in html db in the 10 g environment. I'm trying to create an "auto suggestion function" that predicts values as the user enters characters into a text field. I've gotten it to work by hard coding the values in the function, ie: states. btw: there are several external javascript files at work here.
What I want is to create a dynamic link to the database to gather, say, all names of providers at the time the page is built to use in the auto suggest format. I want to put this into a javascript routine and I'm having problems finding out how to mix the sql select statement into the javascript function.
For the states example, I'm using:
function StateSuggestions() {
this.states = [
"Alabama", "Alaska", "Arizona", "Arkansas",
"California", "Colorado", "Connecticut",..."Wyoming" ];
Can I substitute the hard coded data (states) with a sql select statement such
as:
select name from <dbtable> ???
How does this need to be "wrapped" or containerized?
Thank you. You have a great product in html db and your site is very useful. I appreciate everything you have done to assist us. Again, thank you.

Hi,
You can use TRUNC with 2 arguments to get the first DATE in a month, year, quarter, week, hour, minute, ISO year, ...
SELECT TRUNC ( ADD_MONTHS ( SYSDATE
                           , 12
              , 'MONTH'
              )     AS first_of_month
FROM    dual
;The DATE returned will be in the same month, year, quearter, ... as the first argument.
\We convered the last day of the month in [your previous question|http://forums.oracle.com/forums/message.jspa?messageID=3942939#3942939].
At that time, I warded about using LAST_DAY as a cutoff point; TRUNC is a much better way.
For example, to find all appointment_dates in the current month next year:
SELECT *
FROM    appointments
WHERE   appointment_date >= TRUNC (ADD_MONTHS (SYSDATE, 12), 'MONTH')
AND     appointment_date < TRUNC (ADD_MONTHS (SYSDATE, 13), 'MONTH')Note that
the first part of the WHERE clause calls for dates on or equal to the beginning of the 12th month in the future, but
the second part of the WHERE clause calls for dates before, not equal to , the beginning of the 13th month in the future.

Parsing an OPEN SQL select statement

Hi all,
I want to parse an open SQL select statement to get the list of tables and the corresponding fields in the select statement.
Is there some ABAP-internal syntax from the SAP Database Interface that does this? or is the only option to do this is to manually break the statement?
Thanks.
Girish

Hi,
I doubt if there is something like that available to use. It think you will have to write a parser for yourself.
Regards

Using column number inplace of column name in SQL Select statement

Is there a way to run sql select statements with column numbers in
place of column names?
Current SQL
select AddressId,Name,City from AddressIs this possible
select 1,2,5 from AddressThanks in Advance

user10962462 wrote:
well, ok, it's not possible with SQL, but how about PL/SQL?As mentioned, using DBMS_SQL you can only really use positional notation... and you can also use those positions to get the other information such as what the column is called, what it's datatype is etc.
CREATE OR REPLACE PROCEDURE run_query(p_sql IN VARCHAR2) IS
v_v_val     VARCHAR2(4000);
v_n_val     NUMBER;
v_d_val     DATE;
v_ret       NUMBER;
c           NUMBER;
d           NUMBER;
col_cnt     INTEGER;
f           BOOLEAN;
rec_tab     DBMS_SQL.DESC_TAB;
col_num     NUMBER;
v_rowcount NUMBER := 0;
BEGIN
-- create a cursor
c := DBMS_SQL.OPEN_CURSOR;
-- parse the SQL statement into the cursor
DBMS_SQL.PARSE(c, p_sql, DBMS_SQL.NATIVE);
-- execute the cursor
d := DBMS_SQL.EXECUTE(c);
-- Describe the columns returned by the SQL statement
DBMS_SQL.DESCRIBE_COLUMNS(c, col_cnt, rec_tab);
-- Bind local return variables to the various columns based on their types
FOR j in 1..col_cnt
LOOP
    CASE rec_tab(j).col_type
      WHEN 1 THEN DBMS_SQL.DEFINE_COLUMN(c,j,v_v_val,2000); -- Varchar2
      WHEN 2 THEN DBMS_SQL.DEFINE_COLUMN(c,j,v_n_val);      -- Number
      WHEN 12 THEN DBMS_SQL.DEFINE_COLUMN(c,j,v_d_val);     -- Date
    ELSE
      DBMS_SQL.DEFINE_COLUMN(c,j,v_v_val,2000); -- Any other type return as varchar2
    END CASE;
END LOOP;
-- Display what columns are being returned...
DBMS_OUTPUT.PUT_LINE('-- Columns --');
FOR j in 1..col_cnt
LOOP
    DBMS_OUTPUT.PUT_LINE(rec_tab(j).col_name||' - '||case rec_tab(j).col_type when 1 then 'VARCHAR2'
                                                                              when 2 then 'NUMBER'
                                                                              when 12 then 'DATE'
                                                     else 'Other' end);
END LOOP;
DBMS_OUTPUT.PUT_LINE('-------------');
-- This part outputs the DATA
LOOP
    -- Fetch a row of data through the cursor
    v_ret := DBMS_SQL.FETCH_ROWS(c);
    -- Exit when no more rows
    EXIT WHEN v_ret = 0;
    v_rowcount := v_rowcount + 1;
    DBMS_OUTPUT.PUT_LINE('Row: '||v_rowcount);
    DBMS_OUTPUT.PUT_LINE('--------------');
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    FOR j in 1..col_cnt
    LOOP
      -- Fetch each column into the correct data type based on the description of the column
      CASE rec_tab(j).col_type
        WHEN 1 THEN DBMS_SQL.COLUMN_VALUE(c,j,v_v_val);
                     DBMS_OUTPUT.PUT_LINE(rec_tab(j).col_name||' : '||v_v_val);
        WHEN 2 THEN DBMS_SQL.COLUMN_VALUE(c,j,v_n_val);
                     DBMS_OUTPUT.PUT_LINE(rec_tab(j).col_name||' : '||v_n_val);
        WHEN 12 THEN DBMS_SQL.COLUMN_VALUE(c,j,v_d_val);
                     DBMS_OUTPUT.PUT_LINE(rec_tab(j).col_name||' : '||to_char(v_d_val,'DD/MM/YYYY HH24:MI:SS'));
      ELSE
        DBMS_SQL.COLUMN_VALUE(c,j,v_v_val);
        DBMS_OUTPUT.PUT_LINE(rec_tab(j).col_name||' : '||v_v_val);
      END CASE;
    END LOOP;
    DBMS_OUTPUT.PUT_LINE('--------------');
END LOOP;
-- Close the cursor now we have finished with it
DBMS_SQL.CLOSE_CURSOR(c);
END;
SQL> exec run_query('select empno, ename, deptno, sal from emp where deptno = 10');
-- Columns --
EMPNO - NUMBER
ENAME - VARCHAR2
DEPTNO - NUMBER
SAL - NUMBER
Row: 1
EMPNO : 7782
ENAME : CLARK
DEPTNO : 10
SAL : 2450
Row: 2
EMPNO : 7839
ENAME : KING
DEPTNO : 10
SAL : 5000
Row: 3
EMPNO : 7934
ENAME : MILLER
DEPTNO : 10
SAL : 1300
PL/SQL procedure successfully completed.
SQL> exec run_query('select * from emp where deptno = 10');
-- Columns --
EMPNO - NUMBER
ENAME - VARCHAR2
JOB - VARCHAR2
MGR - NUMBER
HIREDATE - DATE
SAL - NUMBER
COMM - NUMBER
DEPTNO - NUMBER
Row: 1
EMPNO : 7782
ENAME : CLARK
JOB : MANAGER
MGR : 7839
HIREDATE : 09/06/1981 00:00:00
SAL : 2450
COMM :
DEPTNO : 10
Row: 2
EMPNO : 7839
ENAME : KING
JOB : PRESIDENT
MGR :
HIREDATE : 17/11/1981 00:00:00
SAL : 5000
COMM :
DEPTNO : 10
Row: 3
EMPNO : 7934
ENAME : MILLER
JOB : CLERK
MGR : 7782
HIREDATE : 23/01/1982 00:00:00
SAL : 1300
COMM :
DEPTNO : 10
PL/SQL procedure successfully completed.
SQL> exec run_query('select * from dept where deptno = 10');
-- Columns --
DEPTNO - NUMBER
DNAME - VARCHAR2
LOC - VARCHAR2
Row: 1
DEPTNO : 10
DNAME : ACCOUNTING
LOC : NEW YORK
PL/SQL procedure successfully completed.
SQL>

Oracle SQL Select query takes long time than expected.

Hi,
I am facing a problem in SQL select query statement. There is a long time taken in select query from the Database.
The query is as follows.
select /*+rule */ f1.id,f1.fdn,p1.attr_name,p1.attr_value from fdnmappingtable f1,parametertable p1 where p1.id = f1.id and ((f1.object_type ='ne_sub_type.780' )) and ( (f1.id in(select id from fdnmappingtable where fdn like '0=#1#/14=#S0058-3#/17=#S0058-3#/18=#1#/780=#5#%')))order by f1.id asc
This query is taking more than 4 seconds to get the results in a system where the DB is running for more than 1 month.
The same query is taking very few milliseconds (50-100ms) in a system where the DB is freshly installed and the data in the tables are same in both the systems.
Kindly advice what is going wrong??
Regards,
Purushotham

SQL> @/alcatel/omc1/data/query.sql
2 ;
9 rows selected.
Execution Plan
Plan hash value: 3745571015
| Id | Operation | Name |
| 0 | SELECT STATEMENT | |
| 1 | SORT ORDER BY | |
| 2 | NESTED LOOPS | |
| 3 | NESTED LOOPS | |
| 4 | TABLE ACCESS FULL | PARAMETERTABLE |
|* 5 | TABLE ACCESS BY INDEX ROWID| FDNMAPPINGTABLE |
|* 6 | INDEX UNIQUE SCAN | PRIMARY_KY_FDNMAPPINGTABLE |
|* 7 | TABLE ACCESS BY INDEX ROWID | FDNMAPPINGTABLE |
|* 8 | INDEX UNIQUE SCAN | PRIMARY_KY_FDNMAPPINGTABLE |
Predicate Information (identified by operation id):
5 - filter("F1"."OBJECT_TYPE"='ne_sub_type.780')
6 - access("P1"."ID"="F1"."ID")
7 - filter("FDN" LIKE '0=#1#/14=#S0058-3#/17=#S0058-3#/18=#1#/780=#5#
8 - access("F1"."ID"="ID")
Note
- rule based optimizer used (consider using cbo)
Statistics
0 recursive calls
0 db block gets
0 consistent gets
0 physical reads
0 redo size
0 bytes sent via SQL*Net to client
0 bytes received via SQL*Net from client
0 SQL*Net roundtrips to/from client
0 sorts (memory)
0 sorts (disk)
9 rows processed
SQL>

Using if the else logic in regards to a select statement for a report

Hi all,
I've a question regarding if then else logic in Oracle.
I'm developing a report application which contains 3 selectlists
- ProductGroup - SubGroup - Manufacturer
Each one containing several values. And are based on eachother, meaning if you select an item from the PG list, you only get the SG items regarding the PG item you've choosen before. The process logic should be as the following:
When a user selects one item from for example the PG list, the query will be:
select * from x where PG = :P_PG
and the report displays all the items in the PG category selected
The other two bindvariables would be null as the user didn't pick them
If he then proceeds and selects one item from the SG list, the query would be:
select * from x where PG = :P_PG and SG = :P_SG
and the report displays all the items in the PG and SG category selected
If he then proceeds and selects one item from the MA list, the query would be:
select * from x where PG = :P_PG and SG = :P_SG and MA =:P_MA
and the report displays all the items in the PG and SG and MA category selected
Now, I've read some documentation about the decode function, but I can't figure it out, please help.
Peter

Okay, Chet, have set it up on htmldb, so you can see my problem, will go in high detail, it is not producing what I want. Example on htmldb:
DEMO/test
http://htmldb.oracle.com/pls/otn/f?p=33229:6
Defenitions:
3 LOV's, namely:
- LOVPG - select distinct productgroep, productgroep pg from plijst
- LOVSG - select distinct subgroep, subgroep sg from plijst where productgroep = :P6_LOVPG
- LOVLE- select distinct leverancier, leverancier le from plijst where productgroep = :P6_LOVPG and subgroep = :P6_LOVSG
3 Selectitems with submit, namely:
- :P6_LOVPG
- :P6_LOVSG
- :P6_LOVLE
Report region select statement:
select * from plijst where (productgroep = :P6_LOVPG or :P6_LOVPG IS NULL) and (subgroep = :P6_LOVSG or :P6_LOVSG IS NULL) and (leverancier = :P6_LOVLE or :P6_LOVLE IS NULL)
Branch to:
Branche to page on submit after processing
What it should do is:
When you select an item from the first selectlist, productgroep, the report should show all rows containing the specified productgroep.
When the user selects the next item in the subgroep selectlist, the report should show all rows containing the previously selected prodctgroup and the just selected subgroep.
When the user selects the final item , the report should show all rows based on all three selected itemvalues, productgroep, subgroep, leverancier.
The problem is that with this setup the report is only generated after the final selectlist choice of the user. But the user should see a report before that, going deeper into the structure. Hope, you see my problem?
Sincerely,
Pete

Slow query results for simple select statement on Exadata

I have a table with 30+ million rows in it which I'm trying to develop a cube around. When the cube processes (sql analysis), it queries back 10k rows every 6 seconds or so. I ran the same query SQL Analysis runs to grab the data in toad and exported results, and the timing is the same, 10k every 6 seconds or so. r
I ran an execution plan it returns just this:
Plan
SELECT STATEMENT ALL_ROWSCost: 136,019 Bytes: 4,954,594,096 Cardinality: 33,935,576
1 TABLE ACCESS STORAGE FULL TABLE DMSN.DS3R_FH_1XRTT_FA_LVL_KPI Cost: 136,019 Bytes: 4,954,594,096 Cardinality: 33,935,576 I'm not sure if there is a setting in oracle (new to the oracle environment) which can limit performance by connection or user, but if there is, what should I look for and how can I check it.
The Oracle version I'm using is 11.2.0.3.0 and the server is quite large as well (exadata platform). I'm curious because I've seen SQL Server return 100k rows ever 10 seconds before, I would assume an exadata system should return rows a lot quicker. How can I check where the bottle neck is?
Edited by: k1ng87 on Apr 24, 2013 7:58 AM

k1ng87 wrote:
I've notice the same querying speed using Toad (export to CSV)That's not really a good way to test performance. Doing that through Toad, you are getting the database to read the data from it's disks (you don't have a choice in that) shifting bulk amounts of data over your network (that could be a considerable bottleneck) and then letting Toad format the data into CSV format (process the data adding a little bottleneck) and then write the data to another hard disk (more disk I/O = more bottleneck).
I don't know exedata but I imagine it doesn't quite incorporate all those bottlenecks.
and during cube processing via SQL Analysis. How can I check to see if its my network speed thats effecting it?Speak to your technical/networking team, who should be able to trace network activity/packets and see what's happening in that respect.
Is that even possible as our system resides off site, so the traffic is going through multiple networks.Ouch... yes, that could certainly be responsible.
I don't think its the network though because when I run both at the same time, they both are still querying at about 10k rows every 6 seconds.I don't think your performance measuring is accurate. What happens if you actually do the cube in exedata rather than using Toad or SQL Analysis (which I assume is on your client machine?)

Query Regarding Native SQL

Hello Friends,
I am having a requirement to fetch the records from 3 tables( Using inner join)
into an internal table but I am facing a difficulty that I need to fetch the records from this table with entirely different conditions and I need to use ' UNION ALL' Command to fetch the records from the database. For Eg.
I have to write two select statement....
Select <f1> <f2> <f3> <f4>
from <t1> join <t2> join <t3>
into table ITAB
where <Cond. 1>
Select <f1> <f2> <f3> <f4>
from <t1> join <t2> join <t3>
appending table ITAB
where <Cond. 2>
But this is taking two much time... So the user told me to use native SQL to combine this two statement with UNION ALL.. I am using database DB2 Can anyone help me regarding this.
Thanks,
Navneet

HI,
Info in help is good to understand better. Below is the
same for you understanding.
... FROM tabref1 [INNER] JOIN tabref2 ON cond
Effect
The data is to be selected from transparent database tables and/or views determined by tabref1 and tabref2. tabref1 and tabref2 each have the same form as in variant 1 or are themselves Join expressions. The keyword INNER does not have to be specified. The database tables or views determined by tabref1 and tabref2 must be recognized by the ABAP Dictionary.
In a relational data structure, it is quite normal for data that belongs together to be split up across several tables to help the process of standardization (see relational databases). To regroup this information into a database query, you can link tables using the join command. This formulates conditions for the columns in the tables involved. The inner join contains all combinations of lines from the database table determined by tabref1 with lines from the table determined by tabref2, whose values together meet the logical condition (join condition) specified using ON>cond.
Inner join between table 1 and table 2, where column D in both tables in the join condition is set the same:
Table 1 Table 2
A
B
C
D
D
E
F
G
H
a1
b1
c1
1
1
e1
f1
g1
h1
a2
b2
c2
1
3
e2
f2
g2
h2
a3
b3
c3
2
4
e3
f3
g3
h3
a4
b4
c4
3
|--|||--|
Inner Join
A
B
C
D
D
E
F
G
H
a1
b1
c1
1
1
e1
f1
g1
h1
a2
b2
c2
1
1
e1
f1
g1
h1
a4
b4
c4
3
3
e2
f2
g2
h2
|--||||||||--|
Example
Output a list of all flights from Frankfurt to New York between September 10th and 20th, 2001 that are not sold out:
DATA: DATE LIKE SFLIGHT-FLDATE,
CARRID LIKE SFLIGHT-CARRID,
CONNID LIKE SFLIGHT-CONNID.
SELECT FCARRID FCONNID F~FLDATE
INTO (CARRID, CONNID, DATE)
FROM SFLIGHT AS F INNER JOIN SPFLI AS P
ON FCARRID = PCARRID AND
FCONNID = PCONNID
WHERE P~CITYFROM = 'FRANKFURT'
AND P~CITYTO = 'NEW YORK'
AND F~FLDATE BETWEEN '20010910' AND '20010920'
AND FSEATSOCC < FSEATSMAX.
WRITE: / DATE, CARRID, CONNID.
ENDSELECT.
If there are columns with the same name in both tables, you must distinguish between them by prefixing the field descriptor with the table name or a table alias.
Note
In order to determine the result of a SELECT command where the FROM clause contains a join, the database system first creates a temporary table containing the lines that meet the ON condition. The WHERE condition is then applied to the temporary table. It does not matter in an inner join whether the condition is in the ON or WHEREclause. The following example returns the same solution as the previous one.
Example
Output of a list of all flights from Frankfurt to New York between September 10th and 20th, 2001 that are not sold out:
DATA: DATE LIKE SFLIGHT-FLDATE,
CARRID LIKE SFLIGHT-CARRID,
CONNID LIKE SFLIGHT-CONNID.
SELECT FCARRID FCONNID F~FLDATE
INTO (CARRID, CONNID, DATE)
FROM SFLIGHT AS F INNER JOIN SPFLI AS P
ON FCARRID = PCARRID
WHERE FCONNID = PCONNID
AND P~CITYFROM = 'FRANKFURT'
AND P~CITYTO = 'NEW YORK'
AND F~FLDATE BETWEEN '20010910' AND '20010920'
AND FSEATSOCC < FSEATSMAX.
WRITE: / DATE, CARRID, CONNID.
ENDSELECT.
Note
Since not all of the database systems supported by SAP use the standard syntax for ON conditions, the syntax has been restricted. It only allows those joins that produce the same results on all of the supported database systems:
Only a table or view may appear to the right of the JOIN operator, not another join expression.
Only AND is possible in the ON condition as a logical operator.
Each comparison in the ON condition must contain a field from the right-hand table.
If an outer join occurs in the FROM clause, all the ON conditions must contain at least one "real" JOIN condition (a condition that contains a field from tabref1 amd a field from tabref2.
Note
In some cases, '*' may be specified in the SELECT clause, and an internal table or work area is entered into the INTO clause (instead of a list of fields). If so, the fields are written to the target area from left to right in the order in which the tables appear in the FROM clause, according to the structure of each table work area. There can then be gaps between table work areas if you use an Alignment Request. For this reason, you should define the target work area with reference to the types of the database tables, not simply by counting the total number of fields. For an example, see below:
Variant 3
... FROM tabref1 LEFT [OUTER] JOIN tabref2 ON cond
Effect
Selects the data from the transparent database tables and/or views specified in tabref1 and tabref2. tabref1 und tabref2 both have either the same form as in variant 1 or are themselves join expressions. The keyword OUTER can be omitted. The database tables or views specified in tabref1 and tabref2 must be recognized by the ABAP-Dictionary.
In order to determine the result of a SELECT command where the FROM clause contains a left outer join, the database system creates a temporary table containing the lines that meet the ON condition. The remaining fields from the left-hand table (tabref1) are then added to this table, and their corresponding fields from the right-hand table are filled with ZERO values. The system then applies the WHERE condition to the table.
Left outer join between table 1 and table 2 where column D in both tables set the join condition:
Table 1 Table 2
A
B
C
D
D
E
F
G
H
a1
b1
c1
1
1
e1
f1
g1
h1
a2
b2
c2
1
3
e2
f2
g2
h2
a3
b3
c3
2
4
e3
f3
g3
h3
a4
b4
c4
3
|--|||--|
Left Outer Join
A
B
C
D
D
E
F
G
H
a1
b1
c1
1
1
e1
f1
g1
h1
a2
b2
c2
1
1
e1
f1
g1
h1
a3
b3
c3
2
NULL
NULL
NULL
NULL
NULL
a4
b4
c4
3
3
e2
f2
g2
h2
|--||||||||--|
Example
Output a list of all custimers with their bookings for October 15th, 2001:
DATA: CUSTOMER TYPE SCUSTOM,
BOOKING TYPE SBOOK.
SELECT SCUSTOMNAME SCUSTOMPOSTCODE SCUSTOM~CITY
SBOOKFLDATE SBOOKCARRID SBOOKCONNID SBOOKBOOKID
INTO (CUSTOMER-NAME, CUSTOMER-POSTCODE, CUSTOMER-CITY,
BOOKING-FLDATE, BOOKING-CARRID, BOOKING-CONNID,
BOOKING-BOOKID)
FROM SCUSTOM LEFT OUTER JOIN SBOOK
ON SCUSTOMID = SBOOKCUSTOMID AND
SBOOK~FLDATE = '20011015'
ORDER BY SCUSTOMNAME SBOOKFLDATE.
WRITE: / CUSTOMER-NAME, CUSTOMER-POSTCODE, CUSTOMER-CITY,
BOOKING-FLDATE, BOOKING-CARRID, BOOKING-CONNID,
BOOKING-BOOKID.
ENDSELECT.
If there are columns with the same name in both tables, you must distinguish between them by prefixing the field descriptor with the table name or using an alias.
Note
For the resulting set of a SELECT command with a left outer join in the FROM clause, it is generally of crucial importance whether a logical condition is in the ON or WHERE condition. Since not all of the database systems supported by SAP themselves support the standard syntax and semantics of the left outer join, the syntax has been restricted to those cases that return the same solution in all database systems:
Only a table or view may come after the JOIN operator, not another join statement.
The only logical operator allowed in the ON condition is AND.
Each comparison in the ON condition must contain a field from the right-hand table.
Comparisons in the WHERE condition must not contain a field from the right-hand table.
The ON condition must contain at least one "real" JOIN condition (a condition in which a field from tabref1 as well as from tabref2 occurs).
Note
In some cases, '*' may be specivied as the field list in the SELECT clause, and an internal table or work area is entered in the INTO clause (instead of a list of fields). If so, the fields are written to the target area from left to right in the order in which the tables appear in the llen in der FROM clause, according to the structure of each table work area. There can be gaps between the table work areas if you use an Alignment Request. For this reason, you should define the target work area with reference to the types of the database tables, as in the following example (not simply by counting the total number of fields).
Example
Example of a JOIN with more than two tables: Select all flights from Frankfurt to New York between September 10th and 20th, 2001 where there are available places, and display the name of the airline.
DATA: BEGIN OF WA,
FLIGHT TYPE SFLIGHT,
PFLI TYPE SPFLI,
CARR TYPE SCARR,
END OF WA.
SELECT * INTO WA
FROM ( SFLIGHT AS F INNER JOIN SPFLI AS P
ON FCARRID = PCARRID AND
FCONNID = PCONNID )
INNER JOIN SCARR AS C
ON FCARRID = CCARRID
WHERE P~CITYFROM = 'FRANKFURT'
AND P~CITYTO = 'NEW YORK'
AND F~FLDATE BETWEEN '20010910' AND '20010920'
AND FSEATSOCC < FSEATSMAX.
WRITE: / WA-CARR-CARRNAME, WA-FLIGHT-FLDATE, WA-FLIGHT-CARRID,
WA-FLIGHT-CONNID.
ENDSELECT.
Kishore.

SQL 'SELECT' statement

I use LV7.1.1 to read/update an Access Database, using DB Toolset.
When I use the Sql 'SELECT' query with LIKE operator, I do not get any results. (no error is returned).
The statement is:
SELECT Machine, System, AD, Query_Position, RefDesignator, Description
FROM AllLevel
WHERE ((Machine LIKE '*') AND (System LIKE '*') AND (AD ='2000CV20012') AND (Query_Position ='AD') AND (RefDesignator='u1'))
It seems that the LIKE '*' is not translated well by the 'Microsoft Jet 4.0 OLE DB Provider'. I must mention that the statement works just fine under Access, not using LV.
Is there any alternative format for LIKE '*' that do the job?
Regards,
Joseph Moshe

Maybe Access has different syntax, but for T-SQL, the proper syntax for LIKE is to use the % character to match any string of zero or more characters and the _ character to match a single characer. In fact, the documentation says that while * and ? are understood,
"The % and _ (underscore) wildcard characters should be used only
through the Jet OLE DB provider and ActiveX® Data Objects (ADO) code.
They will be treated as literal characters if they are used though the
Access SQL View user interface or Data Access Objects (DAO) code."

Optimizing an SQL Query using Oracle SQL Developer

Hi ,
Currently i am using Oracle SQL Developer as my Database IDE .
Is it possible to use Orqcles SQLDeveloper for the purpose of Optimizing an SQL Query ??
For example assume i am having a query as :
Select from Tranac_Master where CUST_STATAUS='Y' and JCC_REPORT='N'*
Could anybody please tell me how can i use Oracle SQL Developer to optimize this query or any other SQL queries ??
Please share your ideas , thanks in advance .

1. Your query looks very simplistic as it is, so I fail to see how you can better optimise it (unless 'Tranac_Master' is a view, in which case I'd need to see the view details).
2. No tool can automagically optimise your SQL to any degree of practical use. Very minor adjustments may be possible automatically, but really it is a question of you knowing your data & database design accurately, and then you applying your expert knowledge to tune it.

Retrieve floating point data with an sql select statement

Hi
I'm quite new to using sql but I have a system working where I can read and write strings to an access database.
Now I want to retrieve a a float, from a field where another field in the same post corresponds to a specified float, with a select statement.
When using strings I wrote
SELECT column_name FROM [table_name] WHERE column2_name='value'
in my query.
But instead of getting the desired value I get an error message telling me that I have a
"Data type mismatch in criteria expression".
I think I understand why but does anybody know what I should have written instead?

Is the data type of column2_name String? If it's not, I think the single-quotes you have around 'value' will cause that error.
Jim
You're entirely bonkers. But I'll tell you a secret. All the best people are. ~ Alice

Query regarding Oracle SQL select statement

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