How do I get the number of rows a datareader has? I can tell HasRows, but
not how many.
Thanks.
6  8468 
you need to read read to the end with a counter.
a datareader (at least for sqlserver) is a forward only cursor returning
data from the response stream buffer. thus you can not lnow how many rows
there are until you read to the end. on a big query you can read rows while
the server is still performing the query.
this is also why you can not read return paramater from a sp until you've
read all the result sets.
-- bruce (sqlwork.com)
"dew" <de*@yahoo.co m> wrote in message
news:uN******** ******@TK2MSFTN GP09.phx.gbl... How do I get the number of rows a datareader has? I can tell HasRows, but
not how many.
Thanks.
Hello dew,
No way other than iterating through the reader. Sometimes the overhead of
doing this is so much that I have seen people running a count query too,
before/after Read() ing the data, if needed.
You might want to post this question in microsoft.publi c.dotnet.framew ork.adonet.
HTH,
r. How do I get the number of rows a datareader has? I can tell HasRows,
but not how many.
Thanks.
Thanks, all, I guess I'll have to use a dataset.
"dew" <de*@yahoo.co m> wrote in message
news:uN******** ******@TK2MSFTN GP09.phx.gbl... How do I get the number of rows a datareader has? I can tell HasRows, but
not how many.
Thanks.
As one poster has already, commented, you can still use a DataReader. Just
populate it with 2 resultsets, the first one being the count of rows returns.
then use the DataReader's NextResultSet() method to switch to the one
containing all the rows.
Peter
--
Co-founder, Eggheadcafe.com developer portal: http://www.eggheadcafe.com
UnBlog: http://petesbloggerama.blogspot.com
"dew" wrote: How do I get the number of rows a datareader has? I can tell HasRows, but
not how many.
Thanks.
this is really a bad pattern. it requires running the query twice, and if a
row is inserted/deleted between queries, the wrong answer can appear. to
make the query stable you have to use exclusive lock, or select into a temp
table.
-- bruce (sqlwork.com)
"Peter Bromberg [C# MVP]" <pb*******@yaho o.nospammin.com > wrote in message
news:0A******** *************** ***********@mic rosoft.com... As one poster has already, commented, you can still use a DataReader. Just
populate it with 2 resultsets, the first one being the count of rows
returns.
then use the DataReader's NextResultSet() method to switch to the one
containing all the rows.
Peter
--
Co-founder, Eggheadcafe.com developer portal:
http://www.eggheadcafe.com
UnBlog:
http://petesbloggerama.blogspot.com
"dew" wrote:
How do I get the number of rows a datareader has? I can tell HasRows,
but
not how many.
Thanks.
Good point, Bruce, if that precision is critical to the business logic
scenario.
But then, doing so would make it a "good pattern"?
Cheers,
Peter
--
Co-founder, Eggheadcafe.com developer portal: http://www.eggheadcafe.com
UnBlog: http://petesbloggerama.blogspot.com
"Bruce Barker" wrote: this is really a bad pattern. it requires running the query twice, and if a
row is inserted/deleted between queries, the wrong answer can appear. to
make the query stable you have to use exclusive lock, or select into a temp
table.
-- bruce (sqlwork.com)
"Peter Bromberg [C# MVP]" <pb*******@yaho o.nospammin.com > wrote in message
news:0A******** *************** ***********@mic rosoft.com... As one poster has already, commented, you can still use a DataReader. Just
populate it with 2 resultsets, the first one being the count of rows
returns.
then use the DataReader's NextResultSet() method to switch to the one
containing all the rows.
Peter
--
Co-founder, Eggheadcafe.com developer portal:
http://www.eggheadcafe.com
UnBlog:
http://petesbloggerama.blogspot.com
"dew" wrote:
How do I get the number of rows a datareader has? I can tell HasRows,
but
not how many.
Thanks.
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