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1 | 1 | <!-- |
2 | | -$Header: /cvsroot/pgsql/doc/src/sgml/syntax.sgml,v 1.62 2002/06/1521:28:55 tgl Exp $ |
| 2 | +$Header: /cvsroot/pgsql/doc/src/sgml/syntax.sgml,v 1.63 2002/06/1522:15:03 tgl Exp $ |
3 | 3 | --> |
4 | 4 |
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5 | 5 | <chapter id="sql-syntax"> |
@@ -1471,11 +1471,11 @@ SELECT somefunc() OR true; |
1471 | 1471 | be used. For example, this is an untrustworthy way of trying to |
1472 | 1472 | avoid division by zero in a WHERE clause: |
1473 | 1473 | <programlisting> |
1474 | | -SELECT ... WHERE x<> 0 AND y/x> 1.5; |
| 1474 | +SELECT ... WHERE x<> 0 AND y/x> 1.5; |
1475 | 1475 | </programlisting> |
1476 | 1476 | but this is safe: |
1477 | 1477 | <programlisting> |
1478 | | -SELECT ... WHERE CASE WHEN x<> 0 THEN y/x> 1.5 ELSE false END; |
| 1478 | +SELECT ... WHERE CASE WHEN x<> 0 THEN y/x> 1.5 ELSE false END; |
1479 | 1479 | </programlisting> |
1480 | 1480 | A CASE construct used in this fashion will defeat optimization attempts, |
1481 | 1481 | so it should only be done when necessary. |
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