Select IQueryable rows where datatime is null in the database











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I have an IQueryable that is supplied data from a SQL connection. There is a DateTime column in this which can contain nulls. I basically need to be able to get all the rows that have a null datetime value but nothing I am trying seems to work.
This is something like my latest attempt but it just simply fails trying to convert the "null" string to a DateTime format:



IQueryable dataByDate = allData.Where("DateTimeColumnName" + " == @0", (dateValueVariableAsString == null) ? "NULL" : dateValueVariableAsString );


If dateValueVariableAsString has a string with of a valid DateTime format then the I do get the results I expect - however I just cant seem to be able to get the rows where the dateColumn has nulls.






c# datetime null iqueryable







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    I have an IQueryable that is supplied data from a SQL connection. There is a DateTime column in this which can contain nulls. I basically need to be able to get all the rows that have a null datetime value but nothing I am trying seems to work.
    This is something like my latest attempt but it just simply fails trying to convert the "null" string to a DateTime format:



    IQueryable dataByDate = allData.Where("DateTimeColumnName" + " == @0", (dateValueVariableAsString == null) ? "NULL" : dateValueVariableAsString );


    If dateValueVariableAsString has a string with of a valid DateTime format then the I do get the results I expect - however I just cant seem to be able to get the rows where the dateColumn has nulls.






    c# datetime null iqueryable







    share|improve this question


























      up vote
      0
      down vote

      favorite









      up vote
      0
      down vote

      favorite











      I have an IQueryable that is supplied data from a SQL connection. There is a DateTime column in this which can contain nulls. I basically need to be able to get all the rows that have a null datetime value but nothing I am trying seems to work.
      This is something like my latest attempt but it just simply fails trying to convert the "null" string to a DateTime format:



      IQueryable dataByDate = allData.Where("DateTimeColumnName" + " == @0", (dateValueVariableAsString == null) ? "NULL" : dateValueVariableAsString );


      If dateValueVariableAsString has a string with of a valid DateTime format then the I do get the results I expect - however I just cant seem to be able to get the rows where the dateColumn has nulls.






      c# datetime null iqueryable







      share|improve this question















      I have an IQueryable that is supplied data from a SQL connection. There is a DateTime column in this which can contain nulls. I basically need to be able to get all the rows that have a null datetime value but nothing I am trying seems to work.
      This is something like my latest attempt but it just simply fails trying to convert the "null" string to a DateTime format:



      IQueryable dataByDate = allData.Where("DateTimeColumnName" + " == @0", (dateValueVariableAsString == null) ? "NULL" : dateValueVariableAsString );


      If dateValueVariableAsString has a string with of a valid DateTime format then the I do get the results I expect - however I just cant seem to be able to get the rows where the dateColumn has nulls.






      c# datetime null iqueryable




      c# datetime null iqueryable






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      share|improve this question













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      edited 2 days ago

























      asked 2 days ago









      CJH

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          I finally got this sorted with the following alteration to my example above:



          IQueryable dataByDate = allData.Where("DateTimeColumnName == null", null);





          share|improve this answer





















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            1 Answer
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            1 Answer
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            active

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            up vote
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            I finally got this sorted with the following alteration to my example above:



            IQueryable dataByDate = allData.Where("DateTimeColumnName == null", null);





            share|improve this answer

























              up vote
              1
              down vote













              I finally got this sorted with the following alteration to my example above:



              IQueryable dataByDate = allData.Where("DateTimeColumnName == null", null);





              share|improve this answer























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                up vote
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                I finally got this sorted with the following alteration to my example above:



                IQueryable dataByDate = allData.Where("DateTimeColumnName == null", null);





                share|improve this answer












                I finally got this sorted with the following alteration to my example above:



                IQueryable dataByDate = allData.Where("DateTimeColumnName == null", null);






                share|improve this answer












                share|improve this answer



                share|improve this answer










                answered 2 days ago









                CJH

                320315




                320315






























                     

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