Cursor never stops

The name of the pictureThe name of the pictureThe name of the pictureClash Royale CLAN TAG#URR8PPP












1















I appear to have made an error in this cursor and I can't seem to figure out what I have done wrong.



I've confirmed that the select pulls back 2 rows. But when I pass it into the cursor to pick appear the string and I can extract the exact value I need. The two rows look something like the following...



|DATAIDONTWANT|...|DATAIDONTWANT|<|1|DATAIDONTWANT|<|2|DATAIDONTWANT|...|
|DATAIDONTWANT|...|DATAIDONTWANT|<|1|DATAIDONTWANT|<|2|DATAIDONTWANT|...|


The cursor appears to grab the 1st row and continually loop around never getting onto the next row or end the program.



declare
@clobstringP varchar(max),
@clobstring varchar(max);

declare SevenCursor cursor for
select [value] as ClobP
from string_split(@clobstring, '>')
where value like '%<|2|%';

open SevenCursor;
fetch next from SevenCursor into @clobstringP;

while @@FETCH_STATUS = 0
begin
insert into [database].dbo.tablestuff ( ValueP )
select file387
from (
select
RowId387 = row_number() over( order by ( select 1 ) )
,file387 = [value]
from string_split(@clobstringP, '|')
) a
where a.RowId387 = 6;

end;

close SevenCursor;
deallocate SevenCursor;


Can someone point me in the right direction?










share|improve this question




























    1















    I appear to have made an error in this cursor and I can't seem to figure out what I have done wrong.



    I've confirmed that the select pulls back 2 rows. But when I pass it into the cursor to pick appear the string and I can extract the exact value I need. The two rows look something like the following...



    |DATAIDONTWANT|...|DATAIDONTWANT|<|1|DATAIDONTWANT|<|2|DATAIDONTWANT|...|
    |DATAIDONTWANT|...|DATAIDONTWANT|<|1|DATAIDONTWANT|<|2|DATAIDONTWANT|...|


    The cursor appears to grab the 1st row and continually loop around never getting onto the next row or end the program.



    declare
    @clobstringP varchar(max),
    @clobstring varchar(max);

    declare SevenCursor cursor for
    select [value] as ClobP
    from string_split(@clobstring, '>')
    where value like '%<|2|%';

    open SevenCursor;
    fetch next from SevenCursor into @clobstringP;

    while @@FETCH_STATUS = 0
    begin
    insert into [database].dbo.tablestuff ( ValueP )
    select file387
    from (
    select
    RowId387 = row_number() over( order by ( select 1 ) )
    ,file387 = [value]
    from string_split(@clobstringP, '|')
    ) a
    where a.RowId387 = 6;

    end;

    close SevenCursor;
    deallocate SevenCursor;


    Can someone point me in the right direction?










    share|improve this question


























      1












      1








      1








      I appear to have made an error in this cursor and I can't seem to figure out what I have done wrong.



      I've confirmed that the select pulls back 2 rows. But when I pass it into the cursor to pick appear the string and I can extract the exact value I need. The two rows look something like the following...



      |DATAIDONTWANT|...|DATAIDONTWANT|<|1|DATAIDONTWANT|<|2|DATAIDONTWANT|...|
      |DATAIDONTWANT|...|DATAIDONTWANT|<|1|DATAIDONTWANT|<|2|DATAIDONTWANT|...|


      The cursor appears to grab the 1st row and continually loop around never getting onto the next row or end the program.



      declare
      @clobstringP varchar(max),
      @clobstring varchar(max);

      declare SevenCursor cursor for
      select [value] as ClobP
      from string_split(@clobstring, '>')
      where value like '%<|2|%';

      open SevenCursor;
      fetch next from SevenCursor into @clobstringP;

      while @@FETCH_STATUS = 0
      begin
      insert into [database].dbo.tablestuff ( ValueP )
      select file387
      from (
      select
      RowId387 = row_number() over( order by ( select 1 ) )
      ,file387 = [value]
      from string_split(@clobstringP, '|')
      ) a
      where a.RowId387 = 6;

      end;

      close SevenCursor;
      deallocate SevenCursor;


      Can someone point me in the right direction?










      share|improve this question
















      I appear to have made an error in this cursor and I can't seem to figure out what I have done wrong.



      I've confirmed that the select pulls back 2 rows. But when I pass it into the cursor to pick appear the string and I can extract the exact value I need. The two rows look something like the following...



      |DATAIDONTWANT|...|DATAIDONTWANT|<|1|DATAIDONTWANT|<|2|DATAIDONTWANT|...|
      |DATAIDONTWANT|...|DATAIDONTWANT|<|1|DATAIDONTWANT|<|2|DATAIDONTWANT|...|


      The cursor appears to grab the 1st row and continually loop around never getting onto the next row or end the program.



      declare
      @clobstringP varchar(max),
      @clobstring varchar(max);

      declare SevenCursor cursor for
      select [value] as ClobP
      from string_split(@clobstring, '>')
      where value like '%<|2|%';

      open SevenCursor;
      fetch next from SevenCursor into @clobstringP;

      while @@FETCH_STATUS = 0
      begin
      insert into [database].dbo.tablestuff ( ValueP )
      select file387
      from (
      select
      RowId387 = row_number() over( order by ( select 1 ) )
      ,file387 = [value]
      from string_split(@clobstringP, '|')
      ) a
      where a.RowId387 = 6;

      end;

      close SevenCursor;
      deallocate SevenCursor;


      Can someone point me in the right direction?







      sql-server t-sql cursors






      share|improve this question















      share|improve this question













      share|improve this question




      share|improve this question








      edited Jan 23 at 11:41









      Peter Vandivier

      1,0921722




      1,0921722










      asked Jan 23 at 11:00









      TuckRollworthyTuckRollworthy

      243




      243




















          2 Answers
          2






          active

          oldest

          votes


















          0














          As Peter has pointed out, your loop will never end since you don't do a fetch inside the loop. I prefer to have only one FETCH to maintain instead of two. So, my loop structure for a cursor is as follows:



          WHILE 1 = 1
          BEGIN
          FETCH NEXT FROM OrdersCursor INTO @sales_person_id, @orderdate;
          IF @@FETCH_STATUS <> 0
          BREAK

          --Whatever it is I'm doing inside the loop
          END


          A matter of taste which you prefer...






          share|improve this answer






























            5














            The cursor will loop infinitely unless and until @@fetchstatus = 0. In order to reach that state, you need to proceed through the dataset. In order to do that, you should add fetch next from SevenCursor into @clobstringP; to the inside of the begin ... end block so that the cursor has something to iterate over.




            It is perhaps prudent to editorialize a bit at this stage and recommend that you try to ditch the cursor entirely. Cursors are pretty nifty but are misused more often than not; and from your provided psuedo-code, it seems that perhaps you may be trying to fix X when you could bypass to Y.



            I might suggestion taking the whole result set and string_split-ing it into a sensible #temp_table. When you've performed any necessary updates/deletes on this cached result set and verified it's suitable, try for a single insert into dbo.tablestuff ... to succeed or fail based on batch evaluated rules. For example:



            declare @pipe_delimited_rows table ( 
            my_row varchar(max)
            );
            insert @pipe_delimited_rows ( my_row )
            values
            (N'|DATAIDONTWANT|...|DATAIDONTWANT|<|1|DATAIDONTWANT|<|2|DATAIDONTWANT|...|'),
            (N'|DATAIDONTWANT|...|DATAIDONTWANT|<|1|DATAIDONTWANT|<|2|DATAIDONTWANT|...|');

            drop table if exists #cache_results;
            create table #cache_results (
            id int identity not null primary key
            ,ClobP nvarchar(max)
            );

            insert #cache_results ( ClobP )
            select ss.[value] as ClobP
            from @pipe_delimited_rows pdr
            cross apply string_split(pdr.my_row, '>') ss -- delimiting appropriately here, of course
            where ss.[value] like '%<|2|%';

            /* perform business logic to validate interim results here */

            insert into [database].dbo.tablestuff ( ValueP )
            select ClobP
            from #cache_results;



            Disclaimers



            • The sample pseudo-code won't run sensibly as is. I'm kind of patching together from rev 1 of your OP. You'll of course need to delimit on the proper delimiter and perform the appropriate transformations to your live dataset.

            • It's worth noting that there is NO way to enforce order-of-elements within string_split at this time.





            share|improve this answer
























              Your Answer








              StackExchange.ready(function()
              var channelOptions =
              tags: "".split(" "),
              id: "182"
              ;
              initTagRenderer("".split(" "), "".split(" "), channelOptions);

              StackExchange.using("externalEditor", function()
              // Have to fire editor after snippets, if snippets enabled
              if (StackExchange.settings.snippets.snippetsEnabled)
              StackExchange.using("snippets", function()
              createEditor();
              );

              else
              createEditor();

              );

              function createEditor()
              StackExchange.prepareEditor(
              heartbeatType: 'answer',
              autoActivateHeartbeat: false,
              convertImagesToLinks: false,
              noModals: true,
              showLowRepImageUploadWarning: true,
              reputationToPostImages: null,
              bindNavPrevention: true,
              postfix: "",
              imageUploader:
              brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
              contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
              allowUrls: true
              ,
              onDemand: true,
              discardSelector: ".discard-answer"
              ,immediatelyShowMarkdownHelp:true
              );



              );













              draft saved

              draft discarded


















              StackExchange.ready(
              function ()
              StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fdba.stackexchange.com%2fquestions%2f227854%2fcursor-never-stops%23new-answer', 'question_page');

              );

              Post as a guest















              Required, but never shown

























              2 Answers
              2






              active

              oldest

              votes








              2 Answers
              2






              active

              oldest

              votes









              active

              oldest

              votes






              active

              oldest

              votes









              0














              As Peter has pointed out, your loop will never end since you don't do a fetch inside the loop. I prefer to have only one FETCH to maintain instead of two. So, my loop structure for a cursor is as follows:



              WHILE 1 = 1
              BEGIN
              FETCH NEXT FROM OrdersCursor INTO @sales_person_id, @orderdate;
              IF @@FETCH_STATUS <> 0
              BREAK

              --Whatever it is I'm doing inside the loop
              END


              A matter of taste which you prefer...






              share|improve this answer



























                0














                As Peter has pointed out, your loop will never end since you don't do a fetch inside the loop. I prefer to have only one FETCH to maintain instead of two. So, my loop structure for a cursor is as follows:



                WHILE 1 = 1
                BEGIN
                FETCH NEXT FROM OrdersCursor INTO @sales_person_id, @orderdate;
                IF @@FETCH_STATUS <> 0
                BREAK

                --Whatever it is I'm doing inside the loop
                END


                A matter of taste which you prefer...






                share|improve this answer

























                  0












                  0








                  0







                  As Peter has pointed out, your loop will never end since you don't do a fetch inside the loop. I prefer to have only one FETCH to maintain instead of two. So, my loop structure for a cursor is as follows:



                  WHILE 1 = 1
                  BEGIN
                  FETCH NEXT FROM OrdersCursor INTO @sales_person_id, @orderdate;
                  IF @@FETCH_STATUS <> 0
                  BREAK

                  --Whatever it is I'm doing inside the loop
                  END


                  A matter of taste which you prefer...






                  share|improve this answer













                  As Peter has pointed out, your loop will never end since you don't do a fetch inside the loop. I prefer to have only one FETCH to maintain instead of two. So, my loop structure for a cursor is as follows:



                  WHILE 1 = 1
                  BEGIN
                  FETCH NEXT FROM OrdersCursor INTO @sales_person_id, @orderdate;
                  IF @@FETCH_STATUS <> 0
                  BREAK

                  --Whatever it is I'm doing inside the loop
                  END


                  A matter of taste which you prefer...







                  share|improve this answer












                  share|improve this answer



                  share|improve this answer










                  answered Jan 23 at 11:52









                  Tibor KarasziTibor Karaszi

                  1,6906




                  1,6906























                      5














                      The cursor will loop infinitely unless and until @@fetchstatus = 0. In order to reach that state, you need to proceed through the dataset. In order to do that, you should add fetch next from SevenCursor into @clobstringP; to the inside of the begin ... end block so that the cursor has something to iterate over.




                      It is perhaps prudent to editorialize a bit at this stage and recommend that you try to ditch the cursor entirely. Cursors are pretty nifty but are misused more often than not; and from your provided psuedo-code, it seems that perhaps you may be trying to fix X when you could bypass to Y.



                      I might suggestion taking the whole result set and string_split-ing it into a sensible #temp_table. When you've performed any necessary updates/deletes on this cached result set and verified it's suitable, try for a single insert into dbo.tablestuff ... to succeed or fail based on batch evaluated rules. For example:



                      declare @pipe_delimited_rows table ( 
                      my_row varchar(max)
                      );
                      insert @pipe_delimited_rows ( my_row )
                      values
                      (N'|DATAIDONTWANT|...|DATAIDONTWANT|<|1|DATAIDONTWANT|<|2|DATAIDONTWANT|...|'),
                      (N'|DATAIDONTWANT|...|DATAIDONTWANT|<|1|DATAIDONTWANT|<|2|DATAIDONTWANT|...|');

                      drop table if exists #cache_results;
                      create table #cache_results (
                      id int identity not null primary key
                      ,ClobP nvarchar(max)
                      );

                      insert #cache_results ( ClobP )
                      select ss.[value] as ClobP
                      from @pipe_delimited_rows pdr
                      cross apply string_split(pdr.my_row, '>') ss -- delimiting appropriately here, of course
                      where ss.[value] like '%<|2|%';

                      /* perform business logic to validate interim results here */

                      insert into [database].dbo.tablestuff ( ValueP )
                      select ClobP
                      from #cache_results;



                      Disclaimers



                      • The sample pseudo-code won't run sensibly as is. I'm kind of patching together from rev 1 of your OP. You'll of course need to delimit on the proper delimiter and perform the appropriate transformations to your live dataset.

                      • It's worth noting that there is NO way to enforce order-of-elements within string_split at this time.





                      share|improve this answer





























                        5














                        The cursor will loop infinitely unless and until @@fetchstatus = 0. In order to reach that state, you need to proceed through the dataset. In order to do that, you should add fetch next from SevenCursor into @clobstringP; to the inside of the begin ... end block so that the cursor has something to iterate over.




                        It is perhaps prudent to editorialize a bit at this stage and recommend that you try to ditch the cursor entirely. Cursors are pretty nifty but are misused more often than not; and from your provided psuedo-code, it seems that perhaps you may be trying to fix X when you could bypass to Y.



                        I might suggestion taking the whole result set and string_split-ing it into a sensible #temp_table. When you've performed any necessary updates/deletes on this cached result set and verified it's suitable, try for a single insert into dbo.tablestuff ... to succeed or fail based on batch evaluated rules. For example:



                        declare @pipe_delimited_rows table ( 
                        my_row varchar(max)
                        );
                        insert @pipe_delimited_rows ( my_row )
                        values
                        (N'|DATAIDONTWANT|...|DATAIDONTWANT|<|1|DATAIDONTWANT|<|2|DATAIDONTWANT|...|'),
                        (N'|DATAIDONTWANT|...|DATAIDONTWANT|<|1|DATAIDONTWANT|<|2|DATAIDONTWANT|...|');

                        drop table if exists #cache_results;
                        create table #cache_results (
                        id int identity not null primary key
                        ,ClobP nvarchar(max)
                        );

                        insert #cache_results ( ClobP )
                        select ss.[value] as ClobP
                        from @pipe_delimited_rows pdr
                        cross apply string_split(pdr.my_row, '>') ss -- delimiting appropriately here, of course
                        where ss.[value] like '%<|2|%';

                        /* perform business logic to validate interim results here */

                        insert into [database].dbo.tablestuff ( ValueP )
                        select ClobP
                        from #cache_results;



                        Disclaimers



                        • The sample pseudo-code won't run sensibly as is. I'm kind of patching together from rev 1 of your OP. You'll of course need to delimit on the proper delimiter and perform the appropriate transformations to your live dataset.

                        • It's worth noting that there is NO way to enforce order-of-elements within string_split at this time.





                        share|improve this answer



























                          5












                          5








                          5







                          The cursor will loop infinitely unless and until @@fetchstatus = 0. In order to reach that state, you need to proceed through the dataset. In order to do that, you should add fetch next from SevenCursor into @clobstringP; to the inside of the begin ... end block so that the cursor has something to iterate over.




                          It is perhaps prudent to editorialize a bit at this stage and recommend that you try to ditch the cursor entirely. Cursors are pretty nifty but are misused more often than not; and from your provided psuedo-code, it seems that perhaps you may be trying to fix X when you could bypass to Y.



                          I might suggestion taking the whole result set and string_split-ing it into a sensible #temp_table. When you've performed any necessary updates/deletes on this cached result set and verified it's suitable, try for a single insert into dbo.tablestuff ... to succeed or fail based on batch evaluated rules. For example:



                          declare @pipe_delimited_rows table ( 
                          my_row varchar(max)
                          );
                          insert @pipe_delimited_rows ( my_row )
                          values
                          (N'|DATAIDONTWANT|...|DATAIDONTWANT|<|1|DATAIDONTWANT|<|2|DATAIDONTWANT|...|'),
                          (N'|DATAIDONTWANT|...|DATAIDONTWANT|<|1|DATAIDONTWANT|<|2|DATAIDONTWANT|...|');

                          drop table if exists #cache_results;
                          create table #cache_results (
                          id int identity not null primary key
                          ,ClobP nvarchar(max)
                          );

                          insert #cache_results ( ClobP )
                          select ss.[value] as ClobP
                          from @pipe_delimited_rows pdr
                          cross apply string_split(pdr.my_row, '>') ss -- delimiting appropriately here, of course
                          where ss.[value] like '%<|2|%';

                          /* perform business logic to validate interim results here */

                          insert into [database].dbo.tablestuff ( ValueP )
                          select ClobP
                          from #cache_results;



                          Disclaimers



                          • The sample pseudo-code won't run sensibly as is. I'm kind of patching together from rev 1 of your OP. You'll of course need to delimit on the proper delimiter and perform the appropriate transformations to your live dataset.

                          • It's worth noting that there is NO way to enforce order-of-elements within string_split at this time.





                          share|improve this answer















                          The cursor will loop infinitely unless and until @@fetchstatus = 0. In order to reach that state, you need to proceed through the dataset. In order to do that, you should add fetch next from SevenCursor into @clobstringP; to the inside of the begin ... end block so that the cursor has something to iterate over.




                          It is perhaps prudent to editorialize a bit at this stage and recommend that you try to ditch the cursor entirely. Cursors are pretty nifty but are misused more often than not; and from your provided psuedo-code, it seems that perhaps you may be trying to fix X when you could bypass to Y.



                          I might suggestion taking the whole result set and string_split-ing it into a sensible #temp_table. When you've performed any necessary updates/deletes on this cached result set and verified it's suitable, try for a single insert into dbo.tablestuff ... to succeed or fail based on batch evaluated rules. For example:



                          declare @pipe_delimited_rows table ( 
                          my_row varchar(max)
                          );
                          insert @pipe_delimited_rows ( my_row )
                          values
                          (N'|DATAIDONTWANT|...|DATAIDONTWANT|<|1|DATAIDONTWANT|<|2|DATAIDONTWANT|...|'),
                          (N'|DATAIDONTWANT|...|DATAIDONTWANT|<|1|DATAIDONTWANT|<|2|DATAIDONTWANT|...|');

                          drop table if exists #cache_results;
                          create table #cache_results (
                          id int identity not null primary key
                          ,ClobP nvarchar(max)
                          );

                          insert #cache_results ( ClobP )
                          select ss.[value] as ClobP
                          from @pipe_delimited_rows pdr
                          cross apply string_split(pdr.my_row, '>') ss -- delimiting appropriately here, of course
                          where ss.[value] like '%<|2|%';

                          /* perform business logic to validate interim results here */

                          insert into [database].dbo.tablestuff ( ValueP )
                          select ClobP
                          from #cache_results;



                          Disclaimers



                          • The sample pseudo-code won't run sensibly as is. I'm kind of patching together from rev 1 of your OP. You'll of course need to delimit on the proper delimiter and perform the appropriate transformations to your live dataset.

                          • It's worth noting that there is NO way to enforce order-of-elements within string_split at this time.






                          share|improve this answer














                          share|improve this answer



                          share|improve this answer








                          edited Jan 23 at 12:49

























                          answered Jan 23 at 11:38









                          Peter VandivierPeter Vandivier

                          1,0921722




                          1,0921722



























                              draft saved

                              draft discarded
















































                              Thanks for contributing an answer to Database Administrators Stack Exchange!


                              • Please be sure to answer the question. Provide details and share your research!

                              But avoid


                              • Asking for help, clarification, or responding to other answers.

                              • Making statements based on opinion; back them up with references or personal experience.

                              To learn more, see our tips on writing great answers.




                              draft saved


                              draft discarded














                              StackExchange.ready(
                              function ()
                              StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fdba.stackexchange.com%2fquestions%2f227854%2fcursor-never-stops%23new-answer', 'question_page');

                              );

                              Post as a guest















                              Required, but never shown





















































                              Required, but never shown














                              Required, but never shown












                              Required, but never shown







                              Required, but never shown

































                              Required, but never shown














                              Required, but never shown












                              Required, but never shown







                              Required, but never shown






                              Popular posts from this blog

                              How to check contact read email or not when send email to Individual?

                              Displaying single band from multi-band raster using QGIS

                              How many registers does an x86_64 CPU actually have?