Remove <feff> characters and match to latest English version
git-svn-id: https://svn.jboss.org/repos/hibernate/core/trunk@14137 1b8cb986-b30d-0410-93ca-fae66ebed9b2
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<?xml version='1.0' encoding="UTF-8"?>
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<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
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<chapter id="architecture">
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<chapter id="architecture">
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<title>体系结构(Architecture)</title>
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<sect1 id="architecture-overview" revision="1">
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@ -1,7 +1,7 @@
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<?xml version='1.0' encoding="UTF-8"?>
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<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
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<chapter id="associations">
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<chapter id="associations">
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<title>关联关系映射</title>
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@ -1,7 +1,7 @@
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<?xml version='1.0' encoding="UTF-8"?>
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<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
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<chapter id="mapping">
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<chapter id="mapping">
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<title>对象/关系数据库映射基础(Basic O/R Mapping)</title>
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<sect1 id="mapping-declaration" revision="1">
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@ -857,6 +857,171 @@
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</sect3>
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</sect2>
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<sect2 id="mapping-declaration-id-enhanced">
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<title>Enhanced identifier generators</title>
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<para>
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Starting with release 3.2.3, there are 2 new generators which represent a re-thinking of 2 different
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aspects of identifier generation. The first aspect is database portability; the second is optimization
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(not having to query the database for every request for a new identifier value). These two new
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generators are intended to take the place of some of the named generators described above (starting
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in 3.3.x); however, they are included in the current releases and can be referenced by FQN.
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</para>
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<para>
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The first of these new generators is <literal>org.hibernate.id.enhanced.SequenceStyleGenerator</literal>
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which is intended firstly as a replacement for the <literal>sequence</literal> generator and secondly as
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a better portability generator than <literal>native</literal> (because <literal>native</literal>
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(generally) chooses between <literal>identity</literal> and <literal>sequence</literal> which have
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largely different semantics which can cause subtle isssues in applications eyeing portability).
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<literal>org.hibernate.id.enhanced.SequenceStyleGenerator</literal> however achieves portability in
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a different manner. It chooses between using a table or a sequence in the database to store its
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incrementing values depending on the capabilities of the dialect being used. The difference between this
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and <literal>native</literal> is that table-based and sequence-based storage have the same exact
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semantic (in fact sequences are exactly what Hibernate tries to emmulate with its table-based
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generators). This generator has a number of configuration parameters:
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<itemizedlist spacing="compact">
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<listitem>
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<para>
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<literal>sequence_name</literal> (optional, defaults to <literal>hibernate_sequence</literal>):
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The name of the sequence (or table) to be used.
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</para>
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</listitem>
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<listitem>
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<para>
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<literal>initial_value</literal> (optional, defaults to <literal>1</literal>): The initial
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value to be retrieved from the sequence/table. In sequence creation terms, this is analogous
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to the clause typical named "STARTS WITH".
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</para>
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</listitem>
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<listitem>
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<para>
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<literal>increment_size</literal> (optional, defaults to <literal>1</literal>): The value by
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which subsequent calls to the sequence/table should differ. In sequence creation terms, this
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is analogous to the clause typical named "INCREMENT BY".
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</para>
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</listitem>
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<listitem>
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<para>
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<literal>force_table_use</literal> (optional, defaults to <literal>false</literal>): Should
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we force the use of a table as the backing structure even though the dialect might support
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sequence?
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</para>
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</listitem>
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<listitem>
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<para>
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<literal>value_column</literal> (optional, defaults to <literal>next_val</literal>): Only
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relevant for table structures! The name of the column on the table which is used to
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hold the value.
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</para>
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</listitem>
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<listitem>
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<para>
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<literal>optimizer</literal> (optional, defaults to <literal>none</literal>):
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See <xref linkend="mapping-declaration-id-enhanced-optimizers"/>
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</para>
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</listitem>
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</itemizedlist>
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</para>
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<para>
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The second of these new generators is <literal>org.hibernate.id.enhanced.TableGenerator</literal> which
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is intended firstly as a replacement for the <literal>table</literal> generator (although it actually
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functions much more like <literal>org.hibernate.id.MultipleHiLoPerTableGenerator</literal>) and secondly
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as a re-implementation of <literal>org.hibernate.id.MultipleHiLoPerTableGenerator</literal> utilizing the
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notion of pluggable optimiziers. Essentially this generator defines a table capable of holding
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a number of different increment values simultaneously by using multiple distinctly keyed rows. This
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generator has a number of configuration parameters:
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<itemizedlist spacing="compact">
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<listitem>
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<para>
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<literal>table_name</literal> (optional, defaults to <literal>hibernate_sequences</literal>):
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The name of the table to be used.
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</para>
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</listitem>
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<listitem>
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<para>
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<literal>value_column_name</literal> (optional, defaults to <literal>next_val</literal>):
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The name of the column on the table which is used to hold the value.
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</para>
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</listitem>
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<listitem>
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<para>
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<literal>segment_column_name</literal> (optional, defaults to <literal>sequence_name</literal>):
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The name of the column on the table which is used to hold the "segement key". This is the
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value which distinctly identifies which increment value to use.
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</para>
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</listitem>
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<listitem>
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<para>
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<literal>segment_value</literal> (optional, defaults to <literal>default</literal>):
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The "segment key" value for the segment from which we want to pull increment values for
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this generator.
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</para>
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</listitem>
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<listitem>
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<para>
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<literal>segment_value_length</literal> (optional, defaults to <literal>255</literal>):
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Used for schema generation; the column size to create this segment key column.
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</para>
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</listitem>
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<listitem>
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<para>
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<literal>initial_value</literal> (optional, defaults to <literal>1</literal>):
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The initial value to be retrieved from the table.
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</para>
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</listitem>
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<listitem>
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<para>
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<literal>increment_size</literal> (optional, defaults to <literal>1</literal>):
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The value by which subsequent calls to the table should differ.
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</para>
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</listitem>
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<listitem>
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<para>
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<literal>optimizer</literal> (optional, defaults to <literal></literal>):
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See <xref linkend="mapping-declaration-id-enhanced-optimizers"/>
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</para>
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</listitem>
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</itemizedlist>
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</para>
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</sect2>
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<sect2 id="mapping-declaration-id-enhanced-optimizers">
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<title>Identifier generator optimization</title>
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<para>
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For identifier generators which store values in the database, it is inefficient for them to hit the
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database on each and every call to generate a new identifier value. Instead, you'd ideally want to
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group a bunch of them in memory and only hit the database when you have exhausted your in-memory
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value group. This is the role of the pluggable optimizers. Currently only the two enhanced generators
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(<xref linkend="mapping-declaration-id-enhanced"/> support this notion.
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<itemizedlist spacing="compact">
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<listitem>
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<para>
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<literal>none</literal> (generally this is the default if no optimizer was specified): This
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says to not perform any optimizations, and hit the database each and every request.
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</para>
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</listitem>
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<listitem>
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<para>
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<literal>hilo</literal>: applies a hi/lo algorithm around the database retrieved values. The
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values from the database for this optimizer are expected to be sequential. The values
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retrieved from the database structure for this optimizer indicates the "group number"; the
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<literal>increment_size</literal> is multiplied by that value in memory to define a group
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"hi value".
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</para>
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</listitem>
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<listitem>
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<para>
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<literal>pooled</literal>: like was discussed for <literal>hilo</literal>, this optimizers
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attempts to minimize the number of hits to the database. Here, however, we simply store
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the starting value for the "next group" into the database structure rather than a sequential
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value in combination with an in-memory grouping algorithm. <literal>increment_size</literal>
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here refers to the values coming from the database.
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</para>
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</listitem>
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</itemizedlist>
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</para>
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</sect2>
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<sect2 id="mapping-declaration-compositeid" revision="3">
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<title>composite-id</title>
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@ -1,7 +1,7 @@
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<?xml version='1.0' encoding="UTF-8"?>
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<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
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<chapter id="batch">
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<chapter id="batch">
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<title>批量处理（Batch processing）</title>
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<para>
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使用Hibernate将 100 000 条记录插入到数据库的一个很自然的做法可能是这样的
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@ -1,7 +1,7 @@
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<?xml version='1.0' encoding="UTF-8"?>
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<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
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<chapter id="best-practices" revision="2">
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<chapter id="best-practices" revision="2">
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<title>最佳实践(Best Practices)</title>
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<variablelist spacing="compact">
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@ -30,7 +30,6 @@
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对所有的实体都标识出自然键，用<literal><natural-id></literal>进行映射。实现<literal>equals()</literal>和<literal>hashCode()</literal>，在其中用组成自然键的属性进行比较。
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</para>
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</listitem>
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Y00008051221000980 2.7，89，100万
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</varlistentry>
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<varlistentry>
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@ -1,21 +1,17 @@
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<?xml version='1.0' encoding="UTF-8"?>
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<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
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<chapter id="collections">
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<chapter id="collections">
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<title>集合类(Collections)映射</title>
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<sect1 id="collections-persistent" revision="3">
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<title>持久化集合类(Persistent collections)</title>
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<para id="collections-persistent-translate-comment">
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(译者注：在阅读本章的时候，以后整个手册的阅读过程中，我们都会面临一个名词方面的问题，那就是“集合”。"Collections"和"Set"在中文里对应都被翻译为“集合”，但是他们的含义很不一样。Collections是一个超集，Set是其中的一种。大部分情况下，本译稿中泛指的未加英文注明的“集合”，都应当理解为“Collections”。在有些二者同时出现，可能造成混淆的地方，我们用“集合类”来特指“Collecions”,“集合(Set)”来指"Set"，一般都会在后面的括号中给出英文。希望大家在阅读时联系上下文理解，不要造成误解。
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与此同时，“元素”一词对应的英文“element”，也有两个不同的含义。其一为集合的元素，是内存中的一个变量；另一含义则是XML文档中的一个标签所代表的元素。也请注意区别。
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本章中,特别是后半部分是需要反复阅读才能理解清楚的。如果遇到任何疑问,请记住,英文版本的reference是惟一标准的参考资料。)
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</para>
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<para>
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Hibernate要求持久化集合值字段必须声明为接口，比如：
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Hibernate要求持久化集合值字段必须声明为接口，比如：(译者注：在阅读本章的时候，以后整个手册的阅读过程中，我们都会面临一个名词方面的问题，那就是“集合”。"Collections"和"Set"在中文里对应都被翻译为“集合”，但是他们的含义很不一样。Collections是一个超集，Set是其中的一种。大部分情况下，本译稿中泛指的未加英文注明的“集合”，都应当理解为“Collections”。在有些二者同时出现，可能造成混淆的地方，我们用“集合类”来特指“Collecions”,“集合(Set)”来指"Set"，一般都会在后面的括号中给出英文。希望大家在阅读时联系上下文理解，不要造成误解。
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与此同时，“元素”一词对应的英文“element”，也有两个不同的含义。其一为集合的元素，是内存中的一个变量；另一含义则是XML文档中的一个标签所代表的元素。也请注意区别。
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本章中,特别是后半部分是需要反复阅读才能理解清楚的。如果遇到任何疑问,请记住,英文版本的reference是惟一标准的参考资料。)
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</para>
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<programlisting><![CDATA[public class Product {
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@ -725,7 +721,7 @@ LinkedHashMap实现)。 它是在SQL查询中完成排序，而不是在内存
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</class>
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<class name="Item">
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<id name="id" column="ITEM_ID"/>
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<id name="id" column="ITEM_ID"/>
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...
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<!-- inverse end -->
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<?xml version='1.0' encoding="UTF-8"?>
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<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
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<chapter id="components">
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<chapter id="components">
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<title>组件（Component）映射</title>
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<para>
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<?xml version='1.0' encoding="UTF-8"?>
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<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
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<chapter id="session-configuration" revision="1">
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<chapter id="session-configuration" revision="1">
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<title>
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配置
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@ -1,7 +1,7 @@
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<?xml version='1.0' encoding="UTF-8"?>
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<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
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||||
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<chapter id="events">
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<chapter id="events">
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<title>
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拦截器与事件(Interceptors and events)
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</title>
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||||
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<?xml version='1.0' encoding="UTF-8"?>
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<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
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<chapter id="example-mappings">
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<chapter id="example-mappings">
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<title>示例：复杂映射实例</title>
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||||
<para>
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本章展示了一些较为复杂的关系映射。
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@ -1,7 +1,7 @@
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<?xml version='1.0' encoding="UTF-8"?>
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<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
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<chapter id="example-parentchild">
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<chapter id="example-parentchild">
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<title>示例：父子关系(Parent Child Relationships)</title>
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||||
<para>
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刚刚接触Hibernate的人大多是从父子关系（parent / child type relationship）的建模入手的。父子关系的建模有两种方法。由于种种原因，最方便的方法是把<literal>Parent</literal>和<literal>Child</literal>都建模成实体类，并创建一个从<literal>Parent</literal>指向<literal>Child</literal>的<one-to-many>关联，对新手来说尤其如此。还有一种方法，就是将<literal>Child</literal>声明为一个<literal><composite-element></literal>（组合元素）。 事实上在Hibernate中one to many关联的默认语义远没有composite element贴近parent / child关系的通常语义。下面我们会阐述如何使用<emphasis>带有级联的双向一对多关联(bidirectional one to many association with cascades)</emphasis>去建立有效、优美的parent / child关系。这一点也不难！
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@ -223,14 +223,7 @@ parent.addChild(newChild);
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session.update(parent);
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session.flush();]]></programlisting>
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<para>
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Well, that's all very well for the case of a generated identifier, but what about assigned identifiers
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and composite identifiers? This is more difficult, since Hibernate can't use the identifier property to
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distinguish between a newly instantiated object (with an identifier assigned by the user) and an
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object loaded in a previous session. In this case, Hibernate will either use the timestamp or version
|
||||
property, or will actually query the second-level cache or, worst case, the database, to see if the
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||||
row exists.
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</para>
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<para>
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这对于自动生成标识的情况是非常好的，但是自分配的标识和复合标识怎么办呢？这是有点麻烦，因为Hibernate没有办法区分新实例化的对象（标识被用户指定了）和前一个Session装入的对象。在这种情况下，Hibernate会使用timestamp或version属性，或者查询第二级缓存，或者最坏的情况，查询数据库，来确认是否此行存在。</para>
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@ -1,7 +1,7 @@
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<?xml version='1.0' encoding="UTF-8"?>
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<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
|
||||
|
||||
<chapter id="example-weblog">
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<chapter id="example-weblog">
|
||||
<title>示例：Weblog 应用程序</title>
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<sect1 id="example-weblog-classes">
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@ -1,7 +1,7 @@
|
|||
<?xml version='1.0' encoding="UTF-8"?>
|
||||
<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
|
||||
|
||||
<chapter id="filters">
|
||||
<chapter id="filters">
|
||||
<title>过滤数据</title>
|
||||
<para>
|
||||
|
||||
|
|
|
|||
|
|
@ -1,7 +1,7 @@
|
|||
<?xml version='1.0' encoding="UTF-8"?>
|
||||
<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
|
||||
|
||||
<chapter id="inheritance">
|
||||
<chapter id="inheritance">
|
||||
<title>继承映射(Inheritance Mappings)</title>
|
||||
|
||||
<sect1 id="inheritance-strategies" revision="3">
|
||||
|
|
@ -266,7 +266,7 @@
|
|||
</sect2>
|
||||
|
||||
<sect2 id="inheritance-tableperconcreate-polymorphism">
|
||||
<title>Table per concrete class, using implicit polymorphism</title>
|
||||
|
||||
<title>每个具体类一张表，使用隐式多态</title>
|
||||
|
||||
<para>
|
||||
|
|
|
|||
|
|
@ -1,7 +1,7 @@
|
|||
<?xml version='1.0' encoding="UTF-8"?>
|
||||
<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
|
||||
|
||||
<chapter id="performance">
|
||||
<chapter id="performance">
|
||||
<title>提升性能
|
||||
</title>
|
||||
<sect1 id="performance-fetching" revision="2">
|
||||
|
|
@ -609,7 +609,7 @@ Cat fritz = (Cat) iter.next();]]></programlisting>
|
|||
<entry>OSCache</entry>
|
||||
<entry><literal>org.hibernate.cache.OSCacheProvider</literal></entry>
|
||||
<entry>memory, disk</entry>
|
||||
<entry>yes (clustered invalidation)</entry>
|
||||
<entry></entry>
|
||||
<entry>yes</entry>
|
||||
</row>
|
||||
<row>
|
||||
|
|
|
|||
|
|
@ -1,7 +1,7 @@
|
|||
<?xml version='1.0' encoding="UTF-8"?>
|
||||
<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
|
||||
|
||||
<chapter id="persistent-classes" revision="2">
|
||||
<chapter id="persistent-classes" revision="2">
|
||||
<title>持久化类(Persistent Classes)</title>
|
||||
|
||||
<para>
|
||||
|
|
|
|||
|
|
@ -1,7 +1,7 @@
|
|||
<?xml version='1.0' encoding="UTF-8"?>
|
||||
<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
|
||||
|
||||
<chapter id="querycriteria">
|
||||
<chapter id="querycriteria">
|
||||
<title>
|
||||
条件查询(Criteria Queries)
|
||||
</title>
|
||||
|
|
|
|||
|
|
@ -1,7 +1,7 @@
|
|||
<?xml version='1.0' encoding="UTF-8"?>
|
||||
<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
|
||||
|
||||
<chapter id="queryhql">
|
||||
<chapter id="queryhql">
|
||||
<title>HQL: Hibernate查询语言</title>
|
||||
<para>
|
||||
Hibernate配备了一种非常强大的查询语言，这种语言看上去很像SQL。但是不要被语法结构
|
||||
|
|
@ -191,6 +191,42 @@ all properties</literal>
|
|||
|
||||
<programlisting><![CDATA[from Cat as cat where cat.mate.name like '%s%']]></programlisting>
|
||||
</sect1>
|
||||
<sect1 id="queryhql-identifier-property">
|
||||
<title>Refering to identifier property</title>
|
||||
|
||||
<para>
|
||||
There are, generally speaking, 2 ways to refer to an entity's identifier property:
|
||||
</para>
|
||||
<itemizedlist spacing="compact">
|
||||
<listitem>
|
||||
<para>
|
||||
The special property (lowercase) <literal>id</literal> may be used to reference the identifier
|
||||
property of an entity <emphasis>provided that entity does not define a non-identifier property
|
||||
named id</emphasis>.
|
||||
</para>
|
||||
</listitem>
|
||||
<listitem>
|
||||
<para>
|
||||
If the entity defines a named identifier property, you may use that property name.
|
||||
</para>
|
||||
</listitem>
|
||||
</itemizedlist>
|
||||
|
||||
<para>
|
||||
References to composite identifier properties follow the same naming rules. If the
|
||||
entity has a non-identifier property named id, the composite identifier property can only
|
||||
be referenced by its defined named; otherwise, the special <literal>id</literal> property
|
||||
can be used to rerference the identifier property.
|
||||
</para>
|
||||
|
||||
<para>
|
||||
Note: this has changed significantly starting in version 3.2.2. In previous versions,
|
||||
<literal>id</literal> <emphasis>always</emphasis> referred to the identifier property no
|
||||
matter what its actual name. A ramification of that decision was that non-identifier
|
||||
properties named <literal>id</literal> could never be referenced in Hibernate queries.
|
||||
</para>
|
||||
</sect1>
|
||||
|
||||
|
||||
<sect1 id="queryhql-select">
|
||||
<title>select子句</title>
|
||||
|
|
@ -505,6 +541,11 @@ where log.item.class = 'Payment' and log.item.id = payment.id]]></programlisting
|
|||
逻辑运算符<literal>and, or, not</literal>
|
||||
</para>
|
||||
</listitem>
|
||||
<listitem>
|
||||
<para>
|
||||
Parentheses <literal>( )</literal>, indicating grouping
|
||||
</para>
|
||||
</listitem>
|
||||
<listitem>
|
||||
<para>
|
||||
<literal>in</literal>,
|
||||
|
|
@ -856,30 +897,9 @@ from Cat as cat]]></programlisting>
|
|||
注意，HQL自查询只可以在select或者where子句中出现。
|
||||
</para>
|
||||
|
||||
<para>
|
||||
在select列表中包含一个表达式以上的子查询，你可以使用一个元组构造符（tuple constructors）：
|
||||
</para>
|
||||
|
||||
<programlisting><![CDATA[from Cat as cat
|
||||
where not ( cat.name, cat.color ) in (
|
||||
select cat.name, cat.color from DomesticCat cat
|
||||
)]]></programlisting>
|
||||
|
||||
<para>
|
||||
注意在某些数据库中（不包括Oracle与HSQL），你也可以在其他语境中使用元组构造符，
|
||||
比如查询用户类型的组件与组合：
|
||||
</para>
|
||||
|
||||
<programlisting><![CDATA[from Person where name = ('Gavin', 'A', 'King')]]></programlisting>
|
||||
|
||||
<para>
|
||||
该查询等价于更复杂的：
|
||||
</para>
|
||||
|
||||
<programlisting><![CDATA[from Person where name.first = 'Gavin' and name.initial = 'A' and name.last = 'King')]]></programlisting>
|
||||
|
||||
<para>
|
||||
有两个很好的理由使你不应当作这样的事情：首先，它不完全适用于各个数据库平台；其次，查询现在依赖于映射文件中属性的顺序。
|
||||
<para>
|
||||
Note that subqueries can also utilize <literal>row value constructor</literal> syntax. See
|
||||
<xref linkend="queryhql-tuple"/> for more details.
|
||||
</para>
|
||||
|
||||
</sect1>
|
||||
|
|
|
|||
|
|
@ -1,7 +1,7 @@
|
|||
<?xml version='1.0' encoding="UTF-8"?>
|
||||
<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
|
||||
|
||||
<chapter id="querysql" revision="2">
|
||||
<chapter id="querysql" revision="2">
|
||||
<title>Native SQL查询</title>
|
||||
<para>
|
||||
你也可以使用你的数据库的Native SQL语言来查询数据。这对你在要使用数据库的某些特性的时候(比如说在查询提示或者Oracle中的
|
||||
|
|
@ -460,7 +460,7 @@ List pusList = query.setString("name", "Pus%").list(); ]]></programlist
|
|||
FROM PERSON person WHERE person.NAME LIKE :name
|
||||
</sql-query>
|
||||
]]></programlisting>
|
||||
<literal><return-property></literal>也可用于多个字段,它解决了使用<literal>{}</literal>-语法不能细粒度控制多个字段的限制
|
||||
<para><literal><return-property></literal>也可用于多个字段,它解决了使用<literal>{}</literal>-语法不能细粒度控制多个字段的限制</para>
|
||||
<programlisting><![CDATA[<sql-query name="organizationCurrentEmployments">
|
||||
<return alias="emp" class="Employment">
|
||||
<return-property name="salary">
|
||||
|
|
|
|||
|
|
@ -1,7 +1,7 @@
|
|||
<?xml version='1.0' encoding="UTF-8"?>
|
||||
<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
|
||||
|
||||
<chapter id="quickstart">
|
||||
<chapter id="quickstart">
|
||||
<title>在Tomcat中快速上手</title>
|
||||
|
||||
<sect1 id="quickstart-intro" revision="2">
|
||||
|
|
|
|||
|
|
@ -1,7 +1,7 @@
|
|||
<?xml version='1.0' encoding="UTF-8"?>
|
||||
<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
|
||||
|
||||
<chapter id="objectstate">
|
||||
<chapter id="objectstate">
|
||||
|
||||
<title>与对象共事</title>
|
||||
|
||||
|
|
@ -85,7 +85,28 @@ Long generatedId = (Long) sess.save(fritz);]]></programlisting>
|
|||
你也可以按照EJB3 early draft中定义的语义，使用<literal>persist()</literal>替代<literal>save()</literal>。
|
||||
</para>
|
||||
|
||||
|
||||
<itemizedlist spacing="compact">
|
||||
<listitem>
|
||||
<para>
|
||||
<literal>persist()</literal> makes a transient instance persistent.
|
||||
However, it doesn't guarantee that the identifier value will be assigned to
|
||||
the persistent instance immediately, the assignment might happen at flush time.
|
||||
<literal>persist()</literal> also guarantees that it will not execute an
|
||||
<literal>INSERT</literal> statement if it is called outside of transaction
|
||||
boundaries. This is useful in long-running conversations with an extended
|
||||
Session/persistence context.
|
||||
</para>
|
||||
</listitem>
|
||||
<listitem>
|
||||
<para>
|
||||
<literal>save()</literal> does guarantee to return an identifier. If an INSERT
|
||||
has to be executed to get the identifier ( e.g. "identity" generator, not
|
||||
"sequence"), this INSERT happens immediately, no matter if you are inside or
|
||||
outside of a transaction. This is problematic in a long-running conversation
|
||||
with an extended Session/persistence context.
|
||||
</para>
|
||||
</listitem>
|
||||
</itemizedlist>
|
||||
<para>
|
||||
此外，你可以用一个重载版本的<literal>save()</literal>方法。
|
||||
</para>
|
||||
|
|
@ -190,12 +211,13 @@ sess.refresh(cat); //re-read the state (after the trigger executes)]]></programl
|
|||
</sect1>
|
||||
|
||||
<sect1 id="objectstate-querying" revision="1">
|
||||
<title>查询</title>
|
||||
<para>
|
||||
如果不知道所要寻找的对象的持久化标识，那么你需要使用查询。Hibernate支持强大且易于使用的面向对象查询语言(HQL)。
|
||||
如果希望通过编程的方式创建查询，Hibernate提供了完善的按条件(Query By Criteria, QBC)以及按样例(Query By Example, QBE)进行查询的功能。
|
||||
<title>查询</title>
|
||||
|
||||
<para>
|
||||
如果不知道所要寻找的对象的持久化标识，那么你需要使用查询。Hibernate支持强大且易于使用的面向对象查询语言(HQL)。
|
||||
如果希望通过编程的方式创建查询，Hibernate提供了完善的按条件(Query By Criteria, QBC)以及按样例(Query By Example, QBE)进行查询的功能。
|
||||
你也可以用原生SQL(native SQL)描述查询，Hibernate额外提供了将结果集(result set)转化为对象的支持。
|
||||
</para>
|
||||
</para>
|
||||
|
||||
<sect2 id="objectstate-querying-executing" revision="1">
|
||||
<title>执行查询</title>
|
||||
|
|
@ -277,8 +299,8 @@ while ( iter.hasNext() ) {
|
|||
|
||||
while ( kittensAndMothers.hasNext() ) {
|
||||
Object[] tuple = (Object[]) kittensAndMothers.next();
|
||||
Cat kitten = (Cat) tuple[0];
|
||||
Cat mother = (Cat) tuple[1];
|
||||
Cat kitten = (Cat) tuple[0];
|
||||
Cat mother = (Cat) tuple[1];
|
||||
....
|
||||
}]]></programlisting>
|
||||
|
||||
|
|
@ -520,16 +542,16 @@ List cats = crit.list();]]></programlisting>
|
|||
如果你选择使用Hibernate的API, 你必须把SQL别名用大括号包围起来:
|
||||
</para>
|
||||
|
||||
<programlisting><![CDATA[List cats = session.createSQLQuery("SELECT {cat.*} FROM CAT {cat} WHERE ROWNUM<10")
|
||||
.addEntity("cat", Cat.class)
|
||||
.list();]]></programlisting>
|
||||
|
||||
<programlisting><![CDATA[List cats = session.createSQLQuery(
|
||||
"SELECT {cat}.ID AS {cat.id}, {cat}.SEX AS {cat.sex}, " +
|
||||
"{cat}.MATE AS {cat.mate}, {cat}.SUBCLASS AS {cat.class}, ... " +
|
||||
"FROM CAT {cat} WHERE ROWNUM<10")
|
||||
.addEntity("cat", Cat.class)
|
||||
.list()]]></programlisting>
|
||||
<programlisting><![CDATA[List cats = session.createSQLQuery("SELECT {cat.*} FROM CAT {cat} WHERE ROWNUM<10")
|
||||
.addEntity("cat", Cat.class)
|
||||
.list();]]></programlisting>
|
||||
|
||||
<programlisting><![CDATA[List cats = session.createSQLQuery(
|
||||
"SELECT {cat}.ID AS {cat.id}, {cat}.SEX AS {cat.sex}, " +
|
||||
"{cat}.MATE AS {cat.mate}, {cat}.SUBCLASS AS {cat.class}, ... " +
|
||||
"FROM CAT {cat} WHERE ROWNUM<10")
|
||||
.addEntity("cat", Cat.class)
|
||||
.list()]]></programlisting>
|
||||
|
||||
<para>
|
||||
和Hibernate查询一样，SQL查询也可以包含命名参数和占位参数。
|
||||
|
|
|
|||
|
|
@ -185,12 +185,6 @@
|
|||
<entry><literal>foreign-key</literal></entry>
|
||||
<entry><literal>foreign_key_name</literal></entry>
|
||||
<entry>
|
||||
specifies the name of the foreign key constraint generated
|
||||
for an association, for a <literal><one-to-one></literal>,
|
||||
<literal><many-to-one></literal>, <literal><key></literal>,
|
||||
or <literal><many-to-many></literal> mapping element. Note that
|
||||
<literal>inverse="true"</literal> sides will not be considered
|
||||
by <literal>SchemaExport</literal>.
|
||||
指明一个外键的名字，它是为关联生成的，或者<literal><one-to-one></literal>，<literal><many-to-one></literal>, <literal><key></literal>, 或者<literal><many-to-many></literal>映射元素。注意<literal>inverse="true"</literal>在<literal>SchemaExport</literal>时会被忽略。
|
||||
|
||||
</entry>
|
||||
|
|
|
|||
|
|
@ -1,7 +1,7 @@
|
|||
<?xml version='1.0' encoding="UTF-8"?>
|
||||
<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
|
||||
|
||||
<chapter id="transactions" revision="2">
|
||||
<chapter id="transactions" revision="2">
|
||||
<title>事务和并发</title>
|
||||
<para>
|
||||
Hibernate的事务和并发控制很容易掌握。Hibernate直接使用JDBC连接和JTA资源，不添加任何附加锁定
|
||||
|
|
|
|||
|
|
@ -1,7 +1,7 @@
|
|||
<?xml version='1.0' encoding="UTF-8"?>
|
||||
<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
|
||||
|
||||
<chapter id="tutorial">
|
||||
<chapter id="tutorial">
|
||||
<title>
|
||||
Hibernate入门
|
||||
</title>
|
||||
|
|
|
|||
|
|
@ -1,7 +1,7 @@
|
|||
<?xml version='1.0' encoding="UTF-8"?>
|
||||
<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
|
||||
|
||||
<chapter id="xml">
|
||||
<chapter id="xml">
|
||||
<title>XML映射</title>
|
||||
<para><emphasis>
|
||||
注意这是Hibernate 3.0的一个实验性的特性。这一特性仍在积极开发中。
|
||||
|
|
|
|||
Loading…
Reference in New Issue