Hibernate example source code file (portability.po)

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The Hibernate portability.po source code

# translation of Collection_Mapping.po to
# Xi HUANG <xhuang@redhat.com>, 2007, 2010.
msgid ""
msgstr ""
"Project-Id-Version: Collection_Mapping\n"
"Report-Msgid-Bugs-To: http://bugs.kde.org\n"
"POT-Creation-Date: 2010-03-25 06:26+0000\n"
"PO-Revision-Date: 2010-01-20 17:03+1000\n"
"Last-Translator: Xi HUANG <xhuang@redhat.com>\n"
"Language-Team:  <en@li.org>\n"
"MIME-Version: 1.0\n"
"Content-Type: text/plain; charset=UTF-8\n"
"Content-Transfer-Encoding: 8bit\n"
"X-Generator: KBabel 1.11.4\n"

#. Tag: title
#: portability.xml:31
#, no-c-format
msgid "Database Portability Considerations"
msgstr ""

#. Tag: title
#: portability.xml:34
#, no-c-format
msgid "Portability Basics"
msgstr ""

#. Tag: para
#: portability.xml:36
#, no-c-format
msgid ""
"One of the selling points of Hibernate (and really Object/Relational Mapping "
"as a whole) is the notion of database portability. This could mean an "
"internal IT user migrating from one database vendor to another, or it could "
"mean a framework or deployable application consuming Hibernate to "
"simultaneously target multiple database products by their users. Regardless "
"of the exact scenario, the basic idea is that you want Hibernate to help you "
"run against any number of databases without changes to your code, and "
"ideally without any changes to the mapping metadata."
msgstr ""

#. Tag: title
#: portability.xml:47
#, no-c-format
msgid "Dialect"
msgstr ""

#. Tag: para
#: portability.xml:49
#, no-c-format
msgid ""
"The first line of portability for Hibernate is the dialect, which is a "
"specialization of the <classname>org.hibernate.dialect.Dialect "
"contract. A dialect encapsulates all the differences in how Hibernate must "
"communicate with a particular database to accomplish some task like getting "
"a sequence value or structuring a SELECT query. Hibernate bundles a wide "
"range of dialects for many of the most popular databases. If you find that "
"your particular database is not among them, it is not terribly difficult to "
"write your own."
msgstr ""

#. Tag: title
#: portability.xml:60
#, no-c-format
msgid "Dialect resolution"
msgstr ""

#. Tag: para
#: portability.xml:62
#, no-c-format
msgid ""
"Originally, Hibernate would always require that users specify which dialect "
"to use. In the case of users looking to simultaneously target multiple "
"databases with their build that was problematic. Generally this required "
"their users to configure the Hibernate dialect or defining their own method "
"of setting that value."
msgstr ""

#. Tag: para
#: portability.xml:69
#, no-c-format
msgid ""
"Starting with version 3.2, Hibernate introduced the notion of automatically "
"detecting the dialect to use based on the <interfacename>java.sql."
"DatabaseMetaData</interfacename> obtained from a java.sql."
"Connection</interfacename> to that database. This was much better, expect "
"that this resolution was limited to databases Hibernate know about ahead of "
"time and was in no way configurable or overrideable."
msgstr ""

#. Tag: para
#: portability.xml:77
#, no-c-format
msgid ""
"Starting with version 3.3, Hibernate has a fare more powerful way to "
"automatically determine which dialect to should be used by relying on a "
"series of delegates which implement the <interfacename>org.hibernate.dialect."
"resolver.DialectResolver</interfacename> which defines only a single method:"
"<programlisting role=\"JAVA\"> constant on org.hibernate."
"cfg.Environment</classname>)."
msgstr ""

#. Tag: title
#: portability.xml:103
#, no-c-format
msgid "Identifier generation"
msgstr ""

#. Tag: para
#: portability.xml:105
#, no-c-format
msgid ""
"When considering portability between databases, another important decision "
"is selecting the identifier generation stratagy you want to use. Originally "
"Hibernate provided the <emphasis>native generator for this "
"purpose, which was intended to select between a <emphasis>sequenceidentity, or table "
"strategy depending on the capability of the underlying database. However, an "
"insidious implication of this approach comes about when targtetting some "
"databases which support <emphasis>identity generation and some "
"which do not. <emphasis>identity generation relies on the SQL "
"definition of an IDENTITY (or auto-increment) column to manage the "
"identifier value; it is what is known as a post-insert generation strategy "
"becauase the insert must actually happen before we can know the identifier "
"value. Because Hibernate relies on this identifier value to uniquely "
"reference entities within a persistence context it must then issue the "
"insert immediately when the users requests the entitiy be associated with "
"the session (like via save() e.g.) regardless of current transactional "
"semantics. <note>  Hibernate was changed slightly once the implication "
"of this was better understood so that the insert is delayed in cases where "
"that is feasible. </para>  The underlying issue is that the actual "
"semanctics of the application itself changes in these cases."
msgstr ""

#. Tag: para
#: portability.xml:130
#, no-c-format
msgid ""
"Starting with version 3.2.3, Hibernate comes with a set of <ulink url="
"\"http://in.relation.to/2082.lace\">enhanced</ulink> identifier generators "
"targetting portability in a much different way. <note>  There are "
"specifically 2 bundled <emphasis>enhancedgenerators: "
"<itemizedlist>   org.hibernate.id.enhanced."
"SequenceStyleGenerator</classname>     "
"<classname>org.hibernate.id.enhanced.TableGenerator     The idea behind these generators "
"is to port the actual semantics of the identifer value generation to the "
"different databases. For example, the <classname>org.hibernate.id.enhanced."
"SequenceStyleGenerator</classname> mimics the behavior of a sequence on "
"databases which do not support sequences by using a table."
msgstr ""

#. Tag: title
#: portability.xml:159
#, no-c-format
msgid "Database functions"
msgstr ""

#. Tag: para
#: portability.xml:162
#, no-c-format
msgid ""
"This is an area in Hibernate in need of improvement. In terms of portability "
"concerns, this function handling currently works pretty well from HQL; "
"however, it is quite lacking in all other aspects."
msgstr ""

#. Tag: para
#: portability.xml:169
#, no-c-format
msgid ""
"SQL functions can be referenced in many ways by users. However, not all "
"databases support the same set of functions. Hibernate, provides a means of "
"mapping a <emphasis>logical function name to a delegate which "
"knows how to render that particular function, perhaps even using a totally "
"different physical function call."
msgstr ""

#. Tag: para
#: portability.xml:175
#, no-c-format
msgid ""
"Technically this function registration is handled through the <classname>org."
"hibernate.dialect.function.SQLFunctionRegistry</classname> class which is "
"intended to allow users to provide custom function definitions without "
"having to provide a custom dialect. This specific behavior is not fully "
"completed as of yet."
msgstr ""

#. Tag: para
#: portability.xml:182
#, no-c-format
msgid ""
"It is sort of implemented such that users can programatically register "
"functions with the <classname>org.hibernate.cfg.Configuration "
"and those functions will be recognized for HQL."
msgstr ""

#. Tag: title
#: portability.xml:192
#, no-c-format
msgid "Type mappings"
msgstr ""

#. Tag: para
#: portability.xml:194
#, no-c-format
msgid "This section scheduled for completion at a later date..."
msgstr ""

#, fuzzy
#~ msgid ""
#~ "<classname>org.hibernate.id.enhanced.SequenceStyleGenerator"
#~ msgstr ""
#~ "<classname>org.hibernate.id.enhanced.SequenceStyleGenerator"

#, fuzzy
#~ msgid "<classname>org.hibernate.id.enhanced.TableGenerator"
#~ msgstr "<classname>org.hibernate.id.enhanced.TableGenerator"