Output the number of rows returned in a query

How do I find out the number of rows that are returned in a query?
COUNT function I guess can only be used when there is only one table involved. How do I do it for multi table query like JOIN?
For example
SELECT emp.first_name, emp.last_name, jobs.age FROM employees emp, jobs
WHERE emp.employee_id=jobs.employee_id

Hi,
You can get the num of rows info
select count(*) from (SELECT emp.first_name, emp.last_name, jobs.age FROM employees emp, jobs
WHERE emp.employee_id=jobs.employee_id) ;
regards
Jafar
http://www.oracledbarea.blogspot.com

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Getting the number of rows returned from ResultSet

Hi,
Does anyone know a method to get the number of rows returned with a query using the Resultset class?
Thanks.

Hi 281080,
If your database and JDBC driver support it, in order to use the solution that da-alexj has suggested, you need to create a 'scrollable' "ResultSet" -- the javadoc for method "createStatement()" (in class "java.sql.Connection") has more details.
However, I have found with Oracle 8.1.7.4 database and Oracle (thin) JDBC driver, that part of their implementation of the "last()" method (in class "java.sql.ResultSet") is to actually iterate through the entire "ResultSet" in order to reach the last row. If your "ResultSet" is very large (I tested it with a 100,000 row "ResultSet"), this will take a long time.
Just wanted to make you aware of that.
Of-course, this may be irrelevant to you since I didn't see any mention in your post of what database and JDBC driver you are using.
Hope this has helped you, anyway.
Good Luck,
Avi.

Number of rows returned in a query

Is there a way to get the number of rows returned from a query without itterating through the itterator?
Thanks,
Yon

No.
Because rows are not all returned until you start interating.
Some times I have seen people do a count query before the normal query, this helps out if you need a count to set things up.

How can I limit the number of rows returned by a select stat

How can I limit the number of rows returned by a select
statement. I have a query where I return the number of stores
that are located in a given area.. I only want to return the
first twenty-five stores. In some instances there may be over
200 stores in a given location.
I know is SQL 7 that I can set the pagesize to be 25....
Anything similiar in Oracle 8i?
null

Debbie (guest) wrote:
: Chad Nale (guest) wrote:
: : How can I limit the number of rows returned by a select
: : statement. I have a query where I return the number of
: stores
: : that are located in a given area.. I only want to return the
: : first twenty-five stores. In some instances there may be
: over
: : 200 stores in a given location.
: : I know is SQL 7 that I can set the pagesize to be 25....
: : Anything similiar in Oracle 8i?
: If you are in Sql*Plus, you could add the statement
: WHERE rownum <= 25
: Used together with an appropriate ORDER BY you
: could get the first 25 stores.
Watch out. ROWNUM is run before ORDER BY so this would only
order the 25 selected
null

Can I limit the number of rows returned on a Select?

Can I limit the number of rows returned on a Select statement? I would be using JDBC in a Java program.

Use Java prepared statements with the equivalent of this SQL*plus script:
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SELECT rownum FROM all_objects WHERE rownum <= :n;
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         2
         3
EXEC :n := 5;
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         2
         3
         4
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Need to know how to limit the number of rows returned on Oracle

MS SQL Server has a command called 'set row count'.
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I understand that we can use JDBC resultSet object, but that's not what we want.I'm not sure which feature of ResultSet you use and which not.
But if this question has anything to do with JDBC (that's the forum where you put it), I'd recommend to use Statement.setMaxRows(). This will limit the count of rows which your statement will fetch into it's ResultSet.

How do you limit the number of rows return from query?

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i think the standard is limit
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How to get number of rows return in SELECT query

i'm very new in java, i have a question:
- How to get number of rows return in SELECT query?
(i use SQL Server 2000 Driver for JDBC and everything are done, i only want to know problems above)
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make the result set scroll insensitve, do rs.last(), get the row num, and call rs.beforeFirst(), then you can process the result set like you currently do.
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How to restrict number of rows returned in a query

Hi frnds,
I'd like to restrict number of rows returned by my query to some 10 rows. how to do that.When I try doing with the rownum<10 its giving results for a particular dept and that too some 6 rows only...btw I'm grouping my table and includes joins from many a table and am ordering the table results by a column.. How to do this..

776317 wrote:
Hi frnds,
I'd like to restrict number of rows returned by my query to some 10 rows. how to do that.When I try doing with the rownum<10 its giving results for a particular dept and that too some 6 rows only...btw I'm grouping my table and includes joins from many a table and am ordering the table results by a column.. How to do this..
TELL ME HOW MANY ROWS YOU HAVE IN TABLE?
Because you have only *6 rows* in you column, if you less than 10 rows then it displays only containied/exist rows. nothing much
select ename,empno from emp where rownum < 10;Thanks

How to get the number of rows returned by a report?

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Hi. Is there a way to limit the rowsets returned to me in a query? I need to get the first 100, then the next hundred, etc until there are no more rows left to retrieve. Someone told me that I should use a cursor to do this. Does anyone have a specific example? Can this be done with a combination of SQL/JDBC?
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null

if you are talking about limiting the number of rows to be returned to the calling program to a managable number of rowa ...
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see the attached link :
JDBC Code Templates
http://technet.oracle.com/sample_code/tech/java/sqlj_jdbc/htdocs/templates.htm#BatchSize
if you want the server side transaction to only return the first 50 or 100 rows even though the result set has more ... then
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How do you change the number of rows returned by an advanced datagrid...Only displays 1000 rows....I

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Is it possible to count the rows returned from a query?

Hello,
When using JDBC is there anyway of finding out the number of
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null

Pasi Hmlinen (guest) wrote:
: Try
: SELECT COUNT(*) FROM the_table WHERE <conditions>;
: Hope this helps,
: Pasi
Thanks for the advice, I'm currently using SELECT COUNT(*) but
I'm looking for a more efficient way of doing it. If I SELECT
COUNT each time then I have to prepare and execute a SQL
statement each time. What I want to do it execute a single SQL
statement to return my results and somehow find out the number
of rows in the resultset without having to go back to the
database.
Gethin.
null

Output the number of rows returned in a query

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