session_api.po

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">."

#. Tag: title
#: session_api.xml:458
#, no-c-format
msgid "Queries in native SQL"
msgstr "Queries in native SQL"

#. Tag: para
#: session_api.xml:460
#, no-c-format
msgid ""
"You may express a query in SQL, using <literal>createSQLQuery()</literal> "
"and let Hibernate take care of the mapping from result sets to objects. Note "
"that you may at any time call <literal>session.connection()</literal> and "
"use the JDBC <literal>Connection</literal> directly. If you chose to use the "
"Hibernate API, you must enclose SQL aliases in braces:"
msgstr ""
"You may express a query in SQL, using <literal>createSQLQuery()</literal> "
"and let Hibernate take care of the mapping from result sets to objects. Note "
"that you may at any time call <literal>session.connection()</literal> and "
"use the JDBC <literal>Connection</literal> directly. If you chose to use the "
"Hibernate API, you must enclose SQL aliases in braces:"

#. Tag: programlisting
#: session_api.xml:468
#, no-c-format
msgid ""
"<![CDATA[List cats = session.createSQLQuery(\"SELECT {cat.*} FROM CAT {cat} "
"WHERE ROWNUM<10\")\n"
"    .addEntity(\"cat\", Cat.class)\n"
".list();]]>"
msgstr ""

#. Tag: programlisting
#: session_api.xml:470
#, no-c-format
msgid ""
"<![CDATA[List cats = session.createSQLQuery(\n"
"    \"SELECT {cat}.ID AS {cat.id}, {cat}.SEX AS {cat.sex}, \" +\n"
"           \"{cat}.MATE AS {cat.mate}, {cat}.SUBCLASS AS {cat.class}, ... \" "
"+\n"
"    \"FROM CAT {cat} WHERE ROWNUM<10\")\n"
"    .addEntity(\"cat\", Cat.class)\n"
".list()]]>"
msgstr ""

#. Tag: para
#: session_api.xml:472
#, no-c-format
msgid ""
"SQL queries may contain named and positional parameters, just like Hibernate "
"queries. More information about native SQL queries in Hibernate can be found "
"in <xref linkend=\"querysql\"/>."
msgstr ""
"SQL queries may contain named and positional parameters, just like Hibernate "
"queries. More information about native SQL queries in Hibernate can be found "
"in <xref linkend=\"querysql\"/>."

#. Tag: title
#: session_api.xml:483
#, no-c-format
msgid "Modifying persistent objects"
msgstr "Modifying persistent objects"

#. Tag: para
#: session_api.xml:485
#, no-c-format
msgid ""
"<emphasis>Transactional persistent instances</emphasis> (ie. objects loaded, "
"saved, created or queried by the <literal>Session</literal>) may be "
"manipulated by the application and any changes to persistent state will be "
"persisted when the <literal>Session</literal> is <emphasis>flushed</"
"emphasis> (discussed later in this chapter). There is no need to call a "
"particular method (like <literal>update()</literal>, which has a different "
"purpose) to make your modifications persistent. So the most straightforward "
"way to update the state of an object is to <literal>load()</literal> it, and "
"then manipulate it directly, while the <literal>Session</literal> is open:"
msgstr ""
"<emphasis>Transactional persistent instances</emphasis> (ie. objects loaded, "
"saved, created or queried by the <literal>Session</literal>) may be "
"manipulated by the application and any changes to persistent state will be "
"persisted when the <literal>Session</literal> is <emphasis>flushed</"
"emphasis> (discussed later in this chapter). There is no need to call a "
"particular method (like <literal>update()</literal>, which has a different "
"purpose) to make your modifications persistent. So the most straightforward "
"way to update the state of an object is to <literal>load()</literal> it, and "
"then manipulate it directly, while the <literal>Session</literal> is open:"

#. Tag: programlisting
#: session_api.xml:496
#, no-c-format
msgid ""
"<![CDATA[DomesticCat cat = (DomesticCat) sess.load( Cat.class, new Long"
"(69) );\n"
"cat.setName(\"PK\");\n"
"sess.flush();  // changes to cat are automatically detected and persisted]]>"
msgstr ""

#. Tag: para
#: session_api.xml:498
#, no-c-format
msgid ""
"Sometimes this programming model is inefficient since it would require both "
"an SQL <literal>SELECT</literal> (to load an object) and an SQL "
"<literal>UPDATE</literal> (to persist its updated state) in the same "
"session. Therefore Hibernate offers an alternate approach, using detached "
"instances."
msgstr ""
"Sometimes this programming model is inefficient since it would require both "
"an SQL <literal>SELECT</literal> (to load an object) and an SQL "
"<literal>UPDATE</literal> (to persist its updated state) in the same "
"session. Therefore Hibernate offers an alternate approach, using detached "
"instances."

#. Tag: emphasis
#: session_api.xml:506
#, fuzzy, no-c-format
msgid ""
"Note that Hibernate does not offer its own API for direct execution of "
"<literal>UPDATE</literal> or <literal>DELETE</literal> statements. Hibernate "
"is a <emphasis>state management</emphasis> service, you don't have to think "
"in <emphasis>statements</emphasis> to use it. JDBC is a perfect API for "
"executing SQL statements, you can get a JDBC <literal>Connection</literal> "
"at any time by calling <literal>session.connection()</literal>. Furthermore, "
"the notion of mass operations conflicts with object/relational mapping for "
"online transaction processing-oriented applications. Future versions of "
"Hibernate may however provide special mass operation functions. See <xref "
"linkend=\"batch\"/> for some possible batch operation tricks."
msgstr ""
"Note that Hibernate does not offer its own API for direct execution of "
"<placeholder-1/> or <placeholder-2/> statements. Hibernate is a <placeholder-"
"3/> service, you don't have to think in <placeholder-4/> to use it. JDBC is "
"a perfect API for executing SQL statements, you can get a JDBC <placeholder-"
"5/> at any time by calling <placeholder-6/>. Furthermore, the notion of mass "
"operations conflicts with object/relational mapping for online transaction "
"processing-oriented applications. Future versions of Hibernate may however "
"provide special mass operation functions. See <xref linkend=\"batch\"/> for "
"some possible batch operation tricks."

#. Tag: title
#: session_api.xml:521
#, no-c-format
msgid "Modifying detached objects"
msgstr "Modifying detached objects"

#. Tag: para
#: session_api.xml:523
#, no-c-format
msgid ""
"Many applications need to retrieve an object in one transaction, send it to "
"the UI layer for manipulation, then save the changes in a new transaction. "
"Applications that use this kind of approach in a high-concurrency "
"environment usually use versioned data to ensure isolation for the \"long\" "
"unit of work."
msgstr ""
"Many applications need to retrieve an object in one transaction, send it to "
"the UI layer for manipulation, then save the changes in a new transaction. "
"Applications that use this kind of approach in a high-concurrency "
"environment usually use versioned data to ensure isolation for the \"long\" "
"unit of work."

#. Tag: para
#: session_api.xml:530
#, no-c-format
msgid ""
"Hibernate supports this model by providing for reattachment of detached "
"instances using the <literal>Session.update()</literal> or <literal>Session."
"merge()</literal> methods:"
msgstr ""
"Hibernate supports this model by providing for reattachment of detached "
"instances using the <literal>Session.update()</literal> or <literal>Session."
"merge()</literal> methods:"

#. Tag: programlisting
#: session_api.xml:536
#, no-c-format
msgid ""
"<![CDATA[// in the first session\n"
"Cat cat = (Cat) firstSession.load(Cat.class, catId);\n"
"Cat potentialMate = new Cat();\n"
"firstSession.save(potentialMate);\n"
"\n"
"// in a higher layer of the application\n"
"cat.setMate(potentialMate);\n"
"\n"
"// later, in a new session\n"
"secondSession.update(cat);  // update cat\n"
"secondSession.update(mate); // update mate]]>"
msgstr ""

#. Tag: para
#: session_api.xml:538
#, no-c-format
msgid ""
"If the <literal>Cat</literal> with identifier <literal>catId</literal> had "
"already been loaded by <literal>secondSession</literal> when the application "
"tried to reattach it, an exception would have been thrown."
msgstr ""
"If the <literal>Cat</literal> with identifier <literal>catId</literal> had "
"already been loaded by <literal>secondSession</literal> when the application "
"tried to reattach it, an exception would have been thrown."

#. Tag: para
#: session_api.xml:544
#, no-c-format
msgid ""
"Use <literal>update()</literal> if you are sure that the session does not "
"contain an already persistent instance with the same identifier, and "
"<literal>merge()</literal> if you want to merge your modifications at any "
"time without consideration of the state of the session. In other words, "
"<literal>update()</literal> is usually the first method you would call in a "
"fresh session, ensuring that reattachment of your detached instances is the "
"first operation that is executed."
msgstr ""
"Use <literal>update()</literal> if you are sure that the session does not "
"contain an already persistent instance with the same identifier, and "
"<literal>merge()</literal> if you want to merge your modifications at any "
"time without consideration of the state of the session. In other words, "
"<literal>update()</literal> is usually the first method you would call in a "
"fresh session, ensuring that reattachment of your detached instances is the "
"first operation that is executed."

#. Tag: para
#: session_api.xml:553
#, no-c-format
msgid ""
"The application should individually <literal>update()</literal> detached "
"instances reachable from the given detached instance if and <emphasis>only</"
"emphasis> if it wants their state also updated. This can be automated of "
"course, using <emphasis>transitive persistence</emphasis>, see <xref linkend="
"\"objectstate-transitive\"/>."
msgstr ""
"The application should individually <literal>update()</literal> detached "
"instances reachable from the given detached instance if and <emphasis>only</"
"emphasis> if it wants their state also updated. This can be automated of "
"course, using <emphasis>transitive persistence</emphasis>, see <xref linkend="
"\"objectstate-transitive\"/>."

#. Tag: para
#: session_api.xml:560
#, no-c-format
msgid ""
"The <literal>lock()</literal> method also allows an application to "
"reassociate an object with a new session. However, the detached instance has "
"to be unmodified!"
msgstr ""
"The <literal>lock()</literal> method also allows an application to "
"reassociate an object with a new session. However, the detached instance has "
"to be unmodified!"

#. Tag: programlisting
#: session_api.xml:565
#, no-c-format
msgid ""
"<![CDATA[//just reassociate:\n"
"sess.lock(fritz, LockMode.NONE);\n"
"//do a version check, then reassociate:\n"
"sess.lock(izi, LockMode.READ);\n"
"//do a version check, using SELECT ... FOR UPDATE, then reassociate:\n"
"sess.lock(pk, LockMode.UPGRADE);]]>"
msgstr ""

#. Tag: para
#: session_api.xml:567
#, no-c-format
msgid ""
"Note that <literal>lock()</literal> can be used with various "
"<literal>LockMode</literal>s, see the API documentation and the chapter on "
"transaction handling for more information. Reattachment is not the only "
"usecase for <literal>lock()</literal>."
msgstr ""
"Note that <literal>lock()</literal> can be used with various "
"<literal>LockMode</literal>s, see the API documentation and the chapter on "
"transaction handling for more information. Reattachment is not the only "
"usecase for <literal>lock()</literal>."

#. Tag: para
#: session_api.xml:574
#, no-c-format
msgid ""
"Other models for long units of work are discussed in <xref linkend="
"\"transactions-optimistic\"/>."
msgstr ""
"Other models for long units of work are discussed in <xref linkend="
"\"transactions-optimistic\"/>."

#. Tag: title
#: session_api.xml:581
#, no-c-format
msgid "Automatic state detection"
msgstr "Automatic state detection"

#. Tag: para
#: session_api.xml:583
#, no-c-format
msgid ""
"Hibernate users have requested a general purpose method that either saves a "
"transient instance by generating a new identifier or updates/reattaches the "
"detached instances associated with its current identifier. The "
"<literal>saveOrUpdate()</literal> method implements this functionality."
msgstr ""
"Hibernate users have requested a general purpose method that either saves a "
"transient instance by generating a new identifier or updates/reattaches the "
"detached instances associated with its current identifier. The "
"<literal>saveOrUpdate()</literal> method implements this functionality."

#. Tag: programlisting
#: session_api.xml:590
#, no-c-format
msgid ""
"<![CDATA[// in the first session\n"
"Cat cat = (Cat) firstSession.load(Cat.class, catID);\n"
"\n"
"// in a higher tier of the application\n"
"Cat mate = new Cat();\n"
"cat.setMate(mate);\n"
"\n"
"// later, in a new session\n"
"secondSession.saveOrUpdate(cat);   // update existing state (cat has a non-"
"null id)\n"
"secondSession.saveOrUpdate(mate);  // save the new instance (mate has a null "
"id)]]>"
msgstr ""

#. Tag: para
#: session_api.xml:592
#, no-c-format
msgid ""
"The usage and semantics of <literal>saveOrUpdate()</literal> seems to be "
"confusing for new users. Firstly, so long as you are not trying to use "
"instances from one session in another new session, you should not need to "
"use <literal>update()</literal>, <literal>saveOrUpdate()</literal>, or "
"<literal>merge()</literal>. Some whole applications will never use either of "
"these methods."
msgstr ""
"The usage and semantics of <literal>saveOrUpdate()</literal> seems to be "
"confusing for new users. Firstly, so long as you are not trying to use "
"instances from one session in another new session, you should not need to "
"use <literal>update()</literal>, <literal>saveOrUpdate()</literal>, or "
"<literal>merge()</literal>. Some whole applications will never use either of "
"these methods."

#. Tag: para
#: session_api.xml:600
#, no-c-format
msgid ""
"Usually <literal>update()</literal> or <literal>saveOrUpdate()</literal> are "
"used in the following scenario:"
msgstr ""
"Usually <literal>update()</literal> or <literal>saveOrUpdate()</literal> are "
"used in the following scenario:"