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Groups > comp.lang.java.programmer > #37263
| From | Arne Vajhøj <arne@vajhoej.dk> |
|---|---|
| Newsgroups | comp.lang.java.programmer |
| Subject | Re: Which databases are the most used with Java |
| Date | 2017-08-17 18:11 -0400 |
| Organization | Aioe.org NNTP Server |
| Message-ID | <on54a4$1clf$1@gioia.aioe.org> (permalink) |
| References | (4 earlier) <evbk6cFud9oU1@mid.individual.net> <878tins1li.fsf@munus.decebal.nl> <omqchj$3n6$1@news.albasani.net> <on2r27$1ujh$1@gioia.aioe.org> <on5247$q8$1@news.albasani.net> |
On 8/17/2017 5:33 PM, Sebastian wrote: > Am 17.08.2017 um 03:21 schrieb Arne Vajhøj: >> On 8/13/2017 4:24 PM, Sebastian wrote: >>> and >>> surprising things can happen, starting with your mapping from database >>> types to Java SQL types (NUMERIC?, REAL?, DECIMAL?... - and this can >>> change even when updating from version of a driver to another of the >>> same vendor). >> >> ???? >> >> JDBC defines mapping for standard types. >> >> NUMERIC and DECIMAL maps to BigDecimal. >> >> REAL maps to float or Float depending on context. > I did not mean that mapping, but the step before it, concerning > metadata: the mapping of database types (what you put in the CREATE > TABLE statement to define the columns) to standard types, i. e. > constants in java.sql.Types. With Oracle, you may get a description of > all supported data types with DatabaseMetadata.getTypeInfo(), or call > DatabaseMetadata.getColumns() on a table. > Metadata is one of the areas where there's little standardization, and > drivers from different vendors differ to a greater extent. In part this > is understandable, because the type inventories differ so much. But even > when types are practically identical between vendors, you may get > different metadata. For example, in SQL Server DECIMAL and NUMERIC are > synonymous in the database, but still they chose to map them to the two > respective Types constants (which have no such synonymity assumption) > instead of choosing the same target for both. In some other databases, > java.sql.Types.NUMERIC is mapped from some integer type. > > Sorry for the lengthy clarification. I'd like to avoid to get > side-tracked in this thread. I just wanted to point out one possible > pitfall in designing a vendor-independent layer above JDBC. Ah. Yes - DDL or code that use DDL data are probably not very portable. Arne
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Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-13 07:58 +0200
Re: Which databases are the most used with Java Marcel Mueller <news.5.maazl@spamgourmet.org> - 2017-08-13 09:33 +0200
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-13 11:14 +0200
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-13 16:53 -0400
Re: Which databases are the most used with Java Sebastian <nowhere@nirvana.org> - 2017-08-13 09:36 +0200
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-13 11:07 +0200
Re: Which databases are the most used with Java Andreas Leitgeb <avl@logic.at> - 2017-08-13 09:46 +0000
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-13 12:12 +0200
Re: Which databases are the most used with Java Robert Klemme <shortcutter@googlemail.com> - 2017-08-13 17:47 +0200
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-13 19:11 +0200
Re: Which databases are the most used with Java Robert Klemme <shortcutter@googlemail.com> - 2017-08-13 20:26 +0200
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-13 21:30 +0200
Re: Which databases are the most used with Java Martin Gregorie <martin@address-in-sig.invalid> - 2017-08-13 20:00 +0000
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-13 16:43 -0400
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-13 16:42 -0400
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-13 23:18 +0200
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-13 20:41 -0400
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-14 03:04 +0200
Re: Which databases are the most used with Java lewbloch@gmail.com - 2017-08-14 11:12 -0700
Re: Which databases are the most used with Java Eric Douglas <e.d.programmer@gmail.com> - 2017-08-14 12:42 -0700
Re: Which databases are the most used with Java Robert Klemme <shortcutter@googlemail.com> - 2017-08-21 22:25 +0200
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-21 19:50 -0400
Re: Which databases are the most used with Java Eric Douglas <e.d.programmer@gmail.com> - 2017-08-14 13:48 -0700
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-15 07:27 +0200
Re: Which databases are the most used with Java Martin Gregorie <martin@address-in-sig.invalid> - 2017-08-15 10:25 +0000
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-15 14:15 +0200
Re: Which databases are the most used with Java Martin Gregorie <martin@address-in-sig.invalid> - 2017-08-15 14:37 +0000
Re: Which databases are the most used with Java lewbloch@gmail.com - 2017-08-17 14:52 -0700
Re: Which databases are the most used with Java Sebastian <nowhere@nirvana.org> - 2017-08-18 00:09 +0200
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-17 18:14 -0400
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-17 18:19 -0400
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-18 06:43 +0200
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-15 11:02 -0400
Re: Which databases are the most used with Java Patrick Roemer <sangamon@netcologne.de> - 2017-08-15 13:12 +0200
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-15 14:41 +0200
Re: Which databases are the most used with Java Eric Douglas <e.d.programmer@gmail.com> - 2017-08-15 06:11 -0700
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-15 16:33 +0200
Re: Which databases are the most used with Java Eric Douglas <e.d.programmer@gmail.com> - 2017-08-15 08:05 -0700
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-15 18:48 +0200
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-15 11:12 -0400
Re: Which databases are the most used with Java Eric Douglas <e.d.programmer@gmail.com> - 2017-08-15 08:19 -0700
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-15 11:46 -0400
Re: Which databases are the most used with Java Eric Douglas <e.d.programmer@gmail.com> - 2017-08-15 08:43 -0700
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-15 11:51 -0400
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-15 18:38 +0200
Re: Which databases are the most used with Java Patrick Roemer <sangamon@netcologne.de> - 2017-08-15 16:14 +0200
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-15 17:42 +0200
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-15 11:09 -0400
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-15 11:06 -0400
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-15 18:42 +0200
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-16 21:13 -0400
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-17 09:04 +0200
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-17 18:16 -0400
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-18 06:51 +0200
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-18 08:52 -0400
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-18 15:31 +0200
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-18 15:09 -0400
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-18 23:14 +0200
Re: Which databases are the most used with Java Eric Douglas <e.d.programmer@gmail.com> - 2017-08-18 07:15 -0700
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-18 15:16 -0400
Re: Which databases are the most used with Java Sebastian <nowhere@nirvana.org> - 2017-08-13 18:08 +0200
Re: Which databases are the most used with Java Robert Klemme <shortcutter@googlemail.com> - 2017-08-13 20:30 +0200
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-13 21:35 +0200
Re: Which databases are the most used with Java Sebastian <nowhere@nirvana.org> - 2017-08-13 22:24 +0200
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-13 23:33 +0200
Re: Which databases are the most used with Java Robert Klemme <shortcutter@googlemail.com> - 2017-08-14 18:18 +0200
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-15 07:47 +0200
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-16 21:21 -0400
Re: Which databases are the most used with Java Sebastian <nowhere@nirvana.org> - 2017-08-17 23:33 +0200
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-17 18:11 -0400
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-13 23:24 +0200
Re: Which databases are the most used with Java Robert Klemme <shortcutter@googlemail.com> - 2017-08-14 18:14 +0200
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-15 07:45 +0200
Re: Which databases are the most used with Java Sebastian <nowhere@nirvana.org> - 2017-08-13 22:16 +0200
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-13 16:50 -0400
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-13 23:35 +0200
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-13 21:14 -0400
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-14 10:24 +0200
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-13 16:45 -0400
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-13 23:36 +0200
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-13 20:42 -0400
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-14 03:06 +0200
Re: Which databases are the most used with Java lewbloch@gmail.com - 2017-08-13 09:59 -0700
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-13 17:04 -0400
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-14 00:06 +0200
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-14 00:35 +0200
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-13 20:44 -0400
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-14 03:12 +0200
Re: Which databases are the most used with Java Arne Vajhøj <arne@vajhoej.dk> - 2017-08-13 16:59 -0400
Re: Which databases are the most used with Java Joerg Meier <joergmmeier@arcor.de> - 2017-08-16 07:26 +0200
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-16 09:40 +0200
Re: Which databases are the most used with Java Graeme Geldenhuys <graemeg@example.net> - 2017-08-23 00:15 +0100
Re: Which databases are the most used with Java Cecil Westerhof <Cecil@decebal.nl> - 2017-08-23 12:09 +0200
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