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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-13 13:44:03 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-13 13:44:03 +0000 |
commit | 293913568e6a7a86fd1479e1cff8e2ecb58d6568 (patch) | |
tree | fc3b469a3ec5ab71b36ea97cc7aaddb838423a0c /doc/src/sgml/isn.sgml | |
parent | Initial commit. (diff) | |
download | postgresql-16-293913568e6a7a86fd1479e1cff8e2ecb58d6568.tar.xz postgresql-16-293913568e6a7a86fd1479e1cff8e2ecb58d6568.zip |
Adding upstream version 16.2.upstream/16.2
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'doc/src/sgml/isn.sgml')
-rw-r--r-- | doc/src/sgml/isn.sgml | 424 |
1 files changed, 424 insertions, 0 deletions
diff --git a/doc/src/sgml/isn.sgml b/doc/src/sgml/isn.sgml new file mode 100644 index 0000000..ea2aabc --- /dev/null +++ b/doc/src/sgml/isn.sgml @@ -0,0 +1,424 @@ +<!-- doc/src/sgml/isn.sgml --> + +<sect1 id="isn" xreflabel="isn"> + <title>isn — data types for international standard numbers (ISBN, EAN, UPC, etc.)</title> + + <indexterm zone="isn"> + <primary>isn</primary> + </indexterm> + + <para> + The <filename>isn</filename> module provides data types for the following + international product numbering standards: EAN13, UPC, ISBN (books), ISMN + (music), and ISSN (serials). Numbers are validated on input according to a + hard-coded list of prefixes; this list of prefixes is also used to hyphenate + numbers on output. Since new prefixes are assigned from time to time, the + list of prefixes may be out of date. It is hoped that a future version of + this module will obtain the prefix list from one or more tables that + can be easily updated by users as needed; however, at present, the + list can only be updated by modifying the source code and recompiling. + Alternatively, prefix validation and hyphenation support may be + dropped from a future version of this module. + </para> + + <para> + This module is considered <quote>trusted</quote>, that is, it can be + installed by non-superusers who have <literal>CREATE</literal> privilege + on the current database. + </para> + + <sect2 id="isn-data-types"> + <title>Data Types</title> + + <para> + <xref linkend="isn-datatypes"/> shows the data types provided by + the <filename>isn</filename> module. + </para> + + <table id="isn-datatypes"> + <title><filename>isn</filename> Data Types</title> + <tgroup cols="2"> + <colspec colname="col1" colwidth="1*"/> + <colspec colname="col2" colwidth="2*"/> + <thead> + <row> + <entry>Data Type</entry> + <entry>Description</entry> + </row> + </thead> + + <tbody> + <row> + <entry><type>EAN13</type></entry> + <entry> + European Article Numbers, always displayed in the EAN13 display format + </entry> + </row> + + <row> + <entry><type>ISBN13</type></entry> + <entry> + International Standard Book Numbers to be displayed in + the new EAN13 display format + </entry> + </row> + + <row> + <entry><type>ISMN13</type></entry> + <entry> + International Standard Music Numbers to be displayed in + the new EAN13 display format + </entry> + </row> + <row> + <entry><type>ISSN13</type></entry> + <entry> + International Standard Serial Numbers to be displayed in the new + EAN13 display format + </entry> + </row> + <row> + <entry><type>ISBN</type></entry> + <entry> + International Standard Book Numbers to be displayed in the old + short display format + </entry> + </row> + <row> + <entry><type>ISMN</type></entry> + <entry> + International Standard Music Numbers to be displayed in the + old short display format + </entry> + </row> + <row> + <entry><type>ISSN</type></entry> + <entry> + International Standard Serial Numbers to be displayed in the + old short display format + </entry> + </row> + <row> + <entry><type>UPC</type></entry> + <entry> + Universal Product Codes + </entry> + </row> + </tbody> + </tgroup> + </table> + + <para> + Some notes: + </para> + + <orderedlist> + <listitem> + <para>ISBN13, ISMN13, ISSN13 numbers are all EAN13 numbers.</para> + </listitem> + <listitem> + <para>EAN13 numbers aren't always ISBN13, ISMN13 or ISSN13 (some + are).</para> + </listitem> + <listitem> + <para>Some ISBN13 numbers can be displayed as ISBN.</para> + </listitem> + <listitem> + <para>Some ISMN13 numbers can be displayed as ISMN.</para> + </listitem> + <listitem> + <para>Some ISSN13 numbers can be displayed as ISSN.</para> + </listitem> + <listitem> + <para>UPC numbers are a subset of the EAN13 numbers (they are basically + EAN13 without the first <literal>0</literal> digit).</para> + </listitem> + <listitem> + <para>All UPC, ISBN, ISMN and ISSN numbers can be represented as EAN13 + numbers.</para> + </listitem> + </orderedlist> + + <para> + Internally, all these types use the same representation (a 64-bit + integer), and all are interchangeable. Multiple types are provided + to control display formatting and to permit tighter validity checking + of input that is supposed to denote one particular type of number. + </para> + + <para> + The <type>ISBN</type>, <type>ISMN</type>, and <type>ISSN</type> types will display the + short version of the number (ISxN 10) whenever it's possible, and will show + ISxN 13 format for numbers that do not fit in the short version. + The <type>EAN13</type>, <type>ISBN13</type>, <type>ISMN13</type> and + <type>ISSN13</type> types will always display the long version of the ISxN + (EAN13). + </para> + </sect2> + + <sect2 id="isn-casts"> + <title>Casts</title> + + <para> + The <filename>isn</filename> module provides the following pairs of type casts: + </para> + + <itemizedlist> + <listitem> + <para> + ISBN13 <=> EAN13 + </para> + </listitem> + <listitem> + <para> + ISMN13 <=> EAN13 + </para> + </listitem> + <listitem> + <para> + ISSN13 <=> EAN13 + </para> + </listitem> + <listitem> + <para> + ISBN <=> EAN13 + </para> + </listitem> + <listitem> + <para> + ISMN <=> EAN13 + </para> + </listitem> + <listitem> + <para> + ISSN <=> EAN13 + </para> + </listitem> + <listitem> + <para> + UPC <=> EAN13 + </para> + </listitem> + <listitem> + <para> + ISBN <=> ISBN13 + </para> + </listitem> + <listitem> + <para> + ISMN <=> ISMN13 + </para> + </listitem> + <listitem> + <para> + ISSN <=> ISSN13 + </para> + </listitem> + </itemizedlist> + + <para> + When casting from <type>EAN13</type> to another type, there is a run-time + check that the value is within the domain of the other type, and an error + is thrown if not. The other casts are simply relabelings that will + always succeed. + </para> + </sect2> + + <sect2 id="isn-funcs-ops"> + <title>Functions and Operators</title> + + <para> + The <filename>isn</filename> module provides the standard comparison operators, + plus B-tree and hash indexing support for all these data types. In + addition there are several specialized functions; shown in <xref linkend="isn-functions"/>. + In this table, + <type>isn</type> means any one of the module's data types. + </para> + + <table id="isn-functions"> + <title><filename>isn</filename> Functions</title> + <tgroup cols="1"> + <thead> + <row> + <entry role="func_table_entry"><para role="func_signature"> + Function + </para> + <para> + Description + </para></entry> + </row> + </thead> + + <tbody> + <row> + <entry role="func_table_entry"><para role="func_signature"> + <indexterm><primary>isn_weak</primary></indexterm> + <function>isn_weak</function> ( <type>boolean</type> ) + <returnvalue>boolean</returnvalue> + </para> + <para> + Sets the weak input mode, and returns new setting. + </para></entry> + </row> + + <row> + <entry role="func_table_entry"><para role="func_signature"> + <function>isn_weak</function> () + <returnvalue>boolean</returnvalue> + </para> + <para> + Returns the current status of the weak mode. + </para></entry> + </row> + + <row> + <entry role="func_table_entry"><para role="func_signature"> + <indexterm><primary>make_valid</primary></indexterm> + <function>make_valid</function> ( <type>isn</type> ) + <returnvalue>isn</returnvalue> + </para> + <para> + Validates an invalid number (clears the invalid flag). + </para></entry> + </row> + + <row> + <entry role="func_table_entry"><para role="func_signature"> + <indexterm><primary>is_valid</primary></indexterm> + <function>is_valid</function> ( <type>isn</type> ) + <returnvalue>boolean</returnvalue> + </para> + <para> + Checks for the presence of the invalid flag. + </para></entry> + </row> + </tbody> + </tgroup> + </table> + + <para> + <firstterm>Weak</firstterm> mode is used to be able to insert invalid data + into a table. Invalid means the check digit is wrong, not that there are + missing numbers. + </para> + + <para> + Why would you want to use the weak mode? Well, it could be that + you have a huge collection of ISBN numbers, and that there are so many of + them that for weird reasons some have the wrong check digit (perhaps the + numbers were scanned from a printed list and the OCR got the numbers wrong, + perhaps the numbers were manually captured... who knows). Anyway, the point + is you might want to clean the mess up, but you still want to be able to + have all the numbers in your database and maybe use an external tool to + locate the invalid numbers in the database so you can verify the + information and validate it more easily; so for example you'd want to + select all the invalid numbers in the table. + </para> + + <para> + When you insert invalid numbers in a table using the weak mode, the number + will be inserted with the corrected check digit, but it will be displayed + with an exclamation mark (<literal>!</literal>) at the end, for example + <literal>0-11-000322-5!</literal>. This invalid marker can be checked with + the <function>is_valid</function> function and cleared with the + <function>make_valid</function> function. + </para> + + <para> + You can also force the insertion of invalid numbers even when not in the + weak mode, by appending the <literal>!</literal> character at the end of the + number. + </para> + + <para> + Another special feature is that during input, you can write + <literal>?</literal> in place of the check digit, and the correct check digit + will be inserted automatically. + </para> + </sect2> + + <sect2 id="isn-examples"> + <title>Examples</title> + +<programlisting> +--Using the types directly: +SELECT isbn('978-0-393-04002-9'); +SELECT isbn13('0901690546'); +SELECT issn('1436-4522'); + +--Casting types: +-- note that you can only cast from ean13 to another type when the +-- number would be valid in the realm of the target type; +-- thus, the following will NOT work: select isbn(ean13('0220356483481')); +-- but these will: +SELECT upc(ean13('0220356483481')); +SELECT ean13(upc('220356483481')); + +--Create a table with a single column to hold ISBN numbers: +CREATE TABLE test (id isbn); +INSERT INTO test VALUES('9780393040029'); + +--Automatically calculate check digits (observe the '?'): +INSERT INTO test VALUES('220500896?'); +INSERT INTO test VALUES('978055215372?'); + +SELECT issn('3251231?'); +SELECT ismn('979047213542?'); + +--Using the weak mode: +SELECT isn_weak(true); +INSERT INTO test VALUES('978-0-11-000533-4'); +INSERT INTO test VALUES('9780141219307'); +INSERT INTO test VALUES('2-205-00876-X'); +SELECT isn_weak(false); + +SELECT id FROM test WHERE NOT is_valid(id); +UPDATE test SET id = make_valid(id) WHERE id = '2-205-00876-X!'; + +SELECT * FROM test; + +SELECT isbn13(id) FROM test; +</programlisting> + </sect2> + + <sect2 id="isn-bibliography"> + <title>Bibliography</title> + + <para> + The information to implement this module was collected from + several sites, including: + <itemizedlist> + <listitem><para><ulink url="https://www.isbn-international.org/"></ulink></para></listitem> + <listitem><para><ulink url="https://www.issn.org/"></ulink></para></listitem> + <listitem><para><ulink url="https://www.ismn-international.org/"></ulink></para></listitem> + <listitem><para><ulink url="https://www.wikipedia.org/"></ulink></para></listitem> + </itemizedlist> + + The prefixes used for hyphenation were also compiled from: + <itemizedlist> + <listitem><para><ulink url="https://www.gs1.org/standards/id-keys"></ulink></para></listitem> + <listitem><para><ulink url="https://en.wikipedia.org/wiki/List_of_ISBN_identifier_groups"></ulink></para></listitem> + <listitem><para><ulink url="https://www.isbn-international.org/content/isbn-users-manual"></ulink></para></listitem> + <listitem><para><ulink url="https://en.wikipedia.org/wiki/International_Standard_Music_Number"></ulink></para></listitem> + <listitem><para><ulink url="https://www.ismn-international.org/ranges.html"></ulink></para></listitem> + </itemizedlist> + + Care was taken during the creation of the algorithms and they + were meticulously verified against the suggested algorithms + in the official ISBN, ISMN, ISSN User Manuals. + </para> + </sect2> + + <sect2 id="isn-author"> + <title>Author</title> + <para> + Germán Méndez Bravo (Kronuz), 2004–2006 + </para> + + <para> + This module was inspired by Garrett A. Wollman's + <filename>isbn_issn</filename> code. + </para> + </sect2> + +</sect1> |