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[#6194] Add a section to the manual about the Query By Example API

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lukaseder 2017-05-09 11:40:53 +02:00
parent 58f568cfb3
commit b481ab12c0
2 changed files with 96 additions and 0 deletions
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48
jOOQ-manual/src/main/resources/org/jooq/web/manual-3.8.xml
View File

@ -8424,6 +8424,54 @@ row(Date.valueOf('2010-01-01'), new DayToSecond(2)).overlaps(Date.valueOf('2010-
(C <= B) AND (A <= D)]]></sql>
</content>
</section>
<section id="query-by-example">
<title>Query By Example (QBE)</title>
<content><html>
<p>
A popular approach to querying database tables is called <a href="https://en.wikipedia.org/wiki/Query_by_Example">Query by Example</a>, meaning that an "example" of a result record is provided instead of a formal query:
</p>
</html><code-pair>
<text><![CDATA[-- example book record:
ID :
AUTHOR_ID : 1
TITLE :
PUBLISHED_IN: 1970
LANGUAGE_ID : 1
]]></text>
<sql><![CDATA[-- Corresponding query
SELECT *
FROM book
WHERE author_id = 1
AND published_in = 1970
AND language_id = 1]]></sql></code-pair><html>
<p>
The translation from an example record to a query is fairly straight-forward:
</p>
<ul>
<li>If a record attribute is set to a value, then that value is used for an equality predicate</li>
<li>If a record attribute is not set, then that attribute is not used for any predicates</li>
</ul>
<p>
jOOQ knows a simple API called <reference class="org.jooq.impl.DSL" title="DSL.condition(Record)" anchor="#condition-org.jooq.Record-"/>, which translates a <reference class="org.jooq.Record"/> to a <reference class="org.jooq.Condition"/>:
</p>
</html><java><![CDATA[BookRecord book = new BookRecord();
book.setAuthorId(1);
book.setPublishedIn(1970);
book.setLanguageId(1);
Result<BookRecord> books =
DSL.using(configuration)
.selectFrom(BOOK)
.where(condition(book))
.fetch();]]></java>
</content>
</section>
</sections>
</section>

48
jOOQ-manual/src/main/resources/org/jooq/web/manual-3.9.xml
View File

@ -8477,6 +8477,54 @@ row(Date.valueOf('2010-01-01'), new DayToSecond(2)).overlaps(Date.valueOf('2010-
(C <= B) AND (A <= D)]]></sql>
</content>
</section>
<section id="query-by-example">
<title>Query By Example (QBE)</title>
<content><html>
<p>
A popular approach to querying database tables is called <a href="https://en.wikipedia.org/wiki/Query_by_Example">Query by Example</a>, meaning that an "example" of a result record is provided instead of a formal query:
</p>
</html><code-pair>
<text><![CDATA[-- example book record:
ID :
AUTHOR_ID : 1
TITLE :
PUBLISHED_IN: 1970
LANGUAGE_ID : 1
]]></text>
<sql><![CDATA[-- Corresponding query
SELECT *
FROM book
WHERE author_id = 1
AND published_in = 1970
AND language_id = 1]]></sql></code-pair><html>
<p>
The translation from an example record to a query is fairly straight-forward:
</p>
<ul>
<li>If a record attribute is set to a value, then that value is used for an equality predicate</li>
<li>If a record attribute is not set, then that attribute is not used for any predicates</li>
</ul>
<p>
jOOQ knows a simple API called <reference class="org.jooq.impl.DSL" title="DSL.condition(Record)" anchor="#condition-org.jooq.Record-"/>, which translates a <reference class="org.jooq.Record"/> to a <reference class="org.jooq.Condition"/>:
</p>
</html><java><![CDATA[BookRecord book = new BookRecord();
book.setAuthorId(1);
book.setPublishedIn(1970);
book.setLanguageId(1);
Result<BookRecord> books =
DSL.using(configuration)
.selectFrom(BOOK)
.where(condition(book))
.fetch();]]></java>
</content>
</section>
</sections>
</section>