[GENERAL] Count of non-null values per table column

[David Nelson]

Hello list,<br><br>Apologies if this has been asked before. My search only 
turned up ways to list the total non-null values for all columns as a single 
number. I want the count for each column by column.<br><br>I have inherited a 
database consisting of two related huge monolithic tables that lack referential 
integrity between them, or even basic data constraints. One of the problems 
these tables have is every single non-PK column is NULLable. I am trying to 
understand the information that is actually stored and used so that I can 
implement a (hopefully) better design. Towards that end I would like to know 
the count of non-null values in each column per column. In other words I would 
like to get the following output from a table (the numbers are totally made 
up):<br><br>column_name | 
num_values<br>------------+-----------<br>col1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
 |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
5787<br>------------+-----------<br>col2&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
 |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
17<br>------------+-----------<br>col3&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
 |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
567<br>------------+-----------<br>col4&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
 |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
5787<br>------------+-----------<br>col5&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
 |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
143<br>------------+-----------<br>col6&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
 |&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
1<br>------------+-----------<br>...<br><br>Is this possible through one or 
more of the system views, or will I need to write a function to do this? 
Obviously I can just issue multiple SELECT COUNT(column)... statements, but I'd 
rather not.<br><br>Thanks,<br>David                                      

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