Listing both null and not null in mysql query

Posted by tomasz on Stack Overflow See other posts from Stack Overflow or by tomasz
Published on 2009-08-13T09:05:52Z Indexed on 2010/03/29 7:33 UTC
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mysql

|

null

Let's say I have the table

NAME | ID | REF  
foo1 | 1 | NULL  
foo2 | 2 | 1234  
foo2 | 3 | 567  
foo1 | 4 | NULL  
foo3 | 5 | 89

I'd like to count all instances of NULL and NOT NULL in one query so that I can say

NAME | null | not null  
foo1 |  0   |   2  
foo2 |  2   |   0  
foo3 |  0   |   1

I could run these two queries

select NAME,count(*) from TABLE where REF is not null  
select NAME,count(*) from TABLE where REF is null

But I'm sure there must be a simple way to do it in one mysql query.

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