Created
October 16, 2013 02:09
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PostgreSQL NULL comparison
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| =# select (1!=1); | |
| ?column? | |
| ---------- | |
| f | |
| (1 row) | |
| =# select (1=1); | |
| ?column? | |
| ---------- | |
| t | |
| (1 row) | |
| =# select (NULL=NULL); | |
| ?column? | |
| ---------- | |
| (1 row) | |
| =# select (NULL!=NULL); | |
| ?column? | |
| ---------- | |
| (1 row) | |
| =# select (NULL is NOT NULL); | |
| ?column? | |
| ---------- | |
| f | |
| (1 row) | |
| =# select (NULL is NULL); | |
| ?column? | |
| ---------- | |
| t | |
| (1 row) |
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