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Trying to make Java method to get the length of a column

 
Joel Christophel
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Here's what I've tried. The 'rs' variable references a ResultSet object, and the 'meta' variable references a DatabaseMetaData object.



The column I'm trying to access contains 3 rows with the values being "Joel", "Hannah", and "Kevin. Since I'm trying to get the size of the column, my desired return value would be 3, but it's returning 25.
 
Bear Bibeault
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That's because the size of a column is its length. It has nothing whatsoever to do with the number of rows.

In fact, the number of rows has nothing at all to do with a specific column but the table as a whole.

If you want to get the number of rows, you'd do that with a SELECT COUNT(*) statement.
 
Rob Spoor
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If you want to exclude records with NULL values you should replace that COUNT(*) with COUNT(name_of_column).
 
Joel Christophel
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Thanks for the help; it now returns 3. My new method:

 
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