| From: | John Smith <nukemd(at)hotmail(dot)com> |
|---|---|
| To: | "pgsql-odbc(at)postgresql(dot)org" <pgsql-odbc(at)postgresql(dot)org> |
| Subject: | Precision problems with storage of float/double |
| Date: | 2014-06-15 16:51:32 |
| Message-ID: | DUB121-W17AD73873B390AF3AEF384D3170@phx.gbl |
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| Thread: | |
| Lists: | pgsql-odbc |
Hi,
I have found that floats and doubles that I save to the database with the ODBC driver may lose precision. The exact bit pattern of my double/float is not what is actually saved in the database. This causes difficulties in situations where you need to compare current record contents with the actual data that was inserted.
It appears to be related to conversion from the double/float to text before it is sent to the database.
I made a simple patch that appears to fix the issue (by adding more decimal digits in the string conversion), and a test case that tests the issue.
| Attachment | Content-Type | Size |
|---|---|---|
| float-save.patch | application/octet-stream | 638 bytes |
| float-save-test.c | text/plain | 2.8 KB |
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