db5d724986
Thanks to Michael Deck <deckm@cleansoft.com> for the tipoff. Add more examples for language components.
809 lines
24 KiB
Plaintext
809 lines
24 KiB
Plaintext
<chapter id="syntax">
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<title>SQL Syntax</title>
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<abstract>
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<para>
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A description of the general syntax of SQL.
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</para>
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</abstract>
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<para>
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<acronym>SQL</acronym> manipulates sets of data. The language is
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composed of various <firstterm>key words</firstterm>. Arithmetic
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and procedural expressions are allowed. We will cover these topics
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in this chapter; subsequent chapters will include details on data
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types, functions, and operators.
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</para>
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<sect1>
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<title>Key Words</title>
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<para>
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<acronym>SQL92</acronym> defines <firstterm>key words</firstterm>
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for the language
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which have specific meaning. Some key words are
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<firstterm>reserved</firstterm>, which indicates that they are
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restricted to appear in only certain contexts. Other key words are
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<firstterm>not restricted</firstterm>, which indicates that in certain
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contexts they
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have a specific meaning but are not otherwise constrained.
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</para>
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<para>
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<productname>Postgres</productname> implements an extended subset of the
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<acronym>SQL92</acronym> and <acronym>SQL3</acronym> languages. Some language
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elements are not as restricted in this implementation as is
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called for in the language standards, in part due
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to the extensibility features of <productname>Postgres</productname>.
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</para>
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<para>
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Information on <acronym>SQL92</acronym> and <acronym>SQL3</acronym> key words
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is derived from <xref linkend="DATE97" endterm="DATE97">.
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</para>
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<sect2>
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<title>Reserved Key Words</title>
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<para>
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<acronym>SQL92</acronym> and <acronym>SQL3</acronym> have
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<firstterm>reserved key words</firstterm> which are not allowed
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as identifiers and not allowed in any usage other than as fundamental
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tokens in <acronym>SQL</acronym> statements.
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<productname>Postgres</productname> has additional key words
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which have similar restrictions. In particular, these key words
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are not allowed as column or table names, though in some cases
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they are allowed to be column labels (i.e. in AS clauses).
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</para>
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<tip>
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<para>
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Any string can be specified as an identifier if surrounded by
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double quotes (<quote>like this!</quote>). Some care is required since
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such an identifier will be case sensitive
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and will retain embedded whitespace other special characters.
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</para>
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</tip>
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<para>
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The following are <productname>Postgres</productname>
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reserved words which are neither <acronym>SQL92</acronym>
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nor <acronym>SQL3</acronym> reserved words. These are allowed
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to be present as column labels, but not as identifiers:
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<programlisting>
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ABORT ANALYZE
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BINARY
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CLUSTER CONSTRAINT COPY
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DO
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EXPLAIN EXTEND
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LISTEN LOAD LOCK
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MOVE
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NEW NONE NOTIFY
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RESET
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SETOF SHOW
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UNLISTEN UNTIL
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VACUUM VERBOSE
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</programlisting>
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</para>
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<para>
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The following are <productname>Postgres</productname>
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reserved words which are also <acronym>SQL92</acronym>
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or <acronym>SQL3</acronym> reserved words, and which
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are allowed to be present as column labels, but not as identifiers:
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<programlisting>
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CASE COALESCE CROSS CURRENT
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ELSE END
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FALSE FOREIGN
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GLOBAL GROUP
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LOCAL
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NULLIF
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ORDER
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POSITION PRECISION
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TABLE THEN TRANSACTION TRUE
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WHEN
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</programlisting>
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The following are <productname>Postgres</productname>
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reserved words which are also <acronym>SQL92</acronym>
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or <acronym>SQL3</acronym> reserved words:
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<programlisting>
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ADD ALL ALTER AND ANY AS ASC
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BEGIN BETWEEN BOTH BY
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CASCADE CAST CHAR CHARACTER CHECK CLOSE
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COLLATE COLUMN COMMIT CONSTRAINT
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CREATE CURRENT_DATE CURRENT_TIME
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CURRENT_TIMESTAMP CURRENT_USER CURSOR
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DECIMAL DECLARE DEFAULT DELETE DESC DISTINCT DROP
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EXECUTE EXISTS EXTRACT
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FETCH FLOAT FOR FROM FULL
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GRANT
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HAVING
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IN INNER INSERT INTERVAL INTO IS
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JOIN
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LEADING LEFT LIKE LOCAL
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NAMES NATIONAL NATURAL NCHAR NO NOT NULL NUMERIC
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ON OR OUTER
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PARTIAL PRIMARY PRIVILEGES PROCEDURE PUBLIC
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REFERENCES REVOKE RIGHT ROLLBACK
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SELECT SET SUBSTRING
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TO TRAILING TRIM
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UNION UNIQUE UPDATE USER USING
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VALUES VARCHAR VARYING VIEW
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WHERE WITH WORK
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</programlisting>
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</para>
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<para>
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The following are <acronym>SQL92</acronym> reserved key words which
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are not <productname>Postgres</productname> reserved key words, but which
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if used as function names are always translated into the function
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<function>length</function>:
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<programlisting>
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CHAR_LENGTH CHARACTER_LENGTH
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</programlisting>
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</para>
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<para>
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The following are <acronym>SQL92</acronym> or <acronym>SQL3</acronym>
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reserved key words which
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are not <productname>Postgres</productname> reserved key words, but
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if used as type names are always translated into an alternate, native type:
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<programlisting>
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BOOLEAN DOUBLE FLOAT INT INTEGER INTERVAL REAL SMALLINT
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</programlisting>
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</para>
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<para>
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The following are either <acronym>SQL92</acronym>
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or <acronym>SQL3</acronym> reserved key words
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which are not key words in <productname>Postgres</productname>.
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These have no proscribed usage in <productname>Postgres</productname>
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at the time of writing (v6.5) but may become reserved key words in the
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future:
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<note>
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<para>
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Some of these key words represent functions in <acronym>SQL92</acronym>.
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These functions are defined in <productname>Postgres</productname>,
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but the parser does not consider the names to be key words and they are allowed
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in other contexts.
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</para>
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</note>
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<programlisting>
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ALLOCATE ARE ASSERTION AT AUTHORIZATION AVG
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BIT BIT_LENGTH
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CASCADED CATALOG COLLATION CONNECT CONNECTION
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CONSTRAINTS CONTINUE CONVERT CORRESPONDING COUNT
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DATE DEALLOCATE DEC DESCRIBE DESCRIPTOR DIAGNOSTICS DISCONNECT DOMAIN
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END-EXEC ESCAPE EXCEPT EXCEPTION EXEC EXTERNAL
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FIRST FOUND
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GET GO GOTO
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IDENTITY IMMEDIATE INDICATOR INITIALLY INPUT INTERSECT ISOLATION
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LAST LEVEL LOWER
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MAX MIN MODULE
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OCTET_LENGTH OPEN OUTPUT OVERLAPS
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PREPARE PRESERVE
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RESTRICT ROWS
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SCHEMA SECTION SESSION SESSION_USER SIZE SOME
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SQL SQLCODE SQLERROR SQLSTATE SUM SYSTEM_USER
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TEMPORARY TRANSLATE TRANSLATION
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UNKNOWN UPPER USAGE
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VALUE
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WHENEVER WRITE
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</programlisting>
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</para>
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</sect2>
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<sect2>
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<title>Non-reserved Keywords</title>
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<para>
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<acronym>SQL92</acronym> and <acronym>SQL3</acronym> have
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<firstterm>non-reserved keywords</firstterm> which have
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a prescribed meaning in the language but which are also allowed
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as identifiers.
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<productname>Postgres</productname> has additional keywords
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which allow similar unrestricted usage.
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In particular, these keywords
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are allowed as column or table names.
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</para>
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<para>
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The following are <productname>Postgres</productname>
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non-reserved key words which are neither <acronym>SQL92</acronym>
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nor <acronym>SQL3</acronym> non-reserved key words:
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<programlisting>
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ACCESS AFTER AGGREGATE
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BACKWARD BEFORE
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CACHE CREATEDB CREATEUSER CYCLE
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DATABASE DELIMITERS
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EACH ENCODING EXCLUSIVE
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FORWARD FUNCTION
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HANDLER
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INCREMENT INDEX INHERITS INSENSITIVE INSTEAD ISNULL
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LANCOMPILER LOCATION
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MAXVALUE MINVALUE MODE
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NOCREATEDB NOCREATEUSER NOTHING NOTNULL
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OIDS OPERATOR
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PASSWORD PROCEDURAL
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RECIPE RENAME RETURNS ROW RULE
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SEQUENCE SERIAL SHARE START STATEMENT STDIN STDOUT
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TRUSTED
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VALID VERSION
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</programlisting>
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</para>
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<para>
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The following are <productname>Postgres</productname>
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non-reserved key words which are <acronym>SQL92</acronym>
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or <acronym>SQL3</acronym> reserved key words:
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<programlisting>
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ABSOLUTE ACTION
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DAY
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HOUR
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INSENSITIVE
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KEY
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LANGUAGE
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MATCH MINUTE MONTH
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NEXT
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OF ONLY OPTION
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PRIOR PRIVILEGES
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READ RELATIVE
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SCROLL SECOND
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TIME TIMESTAMP TIMEZONE_HOUR TIMEZONE_MINUTE TRIGGER
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YEAR
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ZONE
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</programlisting>
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</para>
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<para>
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The following are <productname>Postgres</productname>
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non-reserved key words which are also either <acronym>SQL92</acronym>
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or <acronym>SQL3</acronym> non-reserved key words:
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<programlisting>
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COMMITTED SERIALIZABLE TYPE
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</programlisting>
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</para>
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<para>
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The following are either <acronym>SQL92</acronym>
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or <acronym>SQL3</acronym> non-reserved key words which are not
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key words of any kind in <productname>Postgres</productname>:
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<programlisting>
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ADA
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C CATALOG_NAME CHARACTER_SET_CATALOG CHARACTER_SET_NAME
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CHARACTER_SET_SCHEMA CLASS_ORIGIN COBOL COLLATION_CATALOG
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COLLATION_NAME COLLATION_SCHEMA COLUMN_NAME
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COMMAND_FUNCTION CONDITION_NUMBER
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CONNECTION_NAME CONSTRAINT_CATALOG CONSTRAINT_NAME
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CONSTRAINT_SCHEMA CURSOR_NAME
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DATA DATE_TIME_INTERVAL_CODE DATE_TIME_INTERVAL_PRECISION
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DYNAMIC_FUNCTION
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FORTRAN
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LENGTH
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MESSAGE_LENGTH MESSAGE_OCTET_LENGTH MORE MUMPS
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NAME NULLABLE NUMBER
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PAD PASCAL PLI
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REPEATABLE RETURNED_LENGTH RETURNED_OCTET_LENGTH
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RETURNED_SQLSTATE ROW_COUNT
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SCALE SCHEMA_NAME SERVER_NAME SPACE
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SUBCLASS_ORIGIN
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TABLE_NAME
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UNCOMMITTED UNNAMED
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</programlisting>
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</para>
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</sect2>
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</sect1>
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<sect1>
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<title>Comments</title>
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<para>
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A <firstterm>comment</firstterm>
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is an arbitrary sequence of characters following double dashes up to the end
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of the line. We also support double-slashes as comments, e.g.:
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<programlisting>
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-- This is a standard SQL comment
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// And this is another supported comment style, like C++
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</programlisting>
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We also support C-style block comments, e.g.:
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<programlisting>
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/* multi
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line
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comment
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*/
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</programlisting>
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</para>
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</sect1>
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<sect1>
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<title>Names</title>
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<para>
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Names in SQL are sequences of less than NAMEDATALEN alphanumeric characters,
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starting with an alphabetic character. By default, NAMEDATALEN is set
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to 32, but at the time the system is built, NAMEDATALEN can be changed
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by changing the <literal>#define</literal> in
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src/backend/include/postgres.h.
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Underscore ("_") is considered an alphabetic character.
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</para>
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<para>
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In some contexts, names may contain other characters if surrounded
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by double quotes. For example, table or column names may contain otherwise
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disallowed characters such as spaces, ampersands, etc. using this
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technique.
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</para>
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</sect1>
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<sect1>
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<title>Constants</title>
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<para>
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There are six types of
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<firstterm>constants</firstterm>
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for use in SQL. They are described below.
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</para>
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<sect2>
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<title>String Constants</title>
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<para>
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<firstterm>Strings</firstterm>
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in SQL are arbitrary sequences of ASCII characters bounded by single
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quotes ("'", e.g. <literal>'This is a string'</literal>).
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Uppercase alphabetics within strings are accepted
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literally. Non-printing characters may be embedded within strings by
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prepending them with a backslash
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("\"; e.g. "\<replaceable>tab</replaceable>".
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SQL92 allows single quotes to be embedded in strings by typing two
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adjacent single quotes (e.g. 'Dianne''s horse'), and for
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historical reasons <productname>Postgres</productname> also allows
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single quotes to be escaped with a backslash
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(e.g. 'Dianne\'s horse').
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</para>
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<para>
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Because of the limitations on
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instance sizes, string constants are currently limited to a length of
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a little less than 8192 bytes. Larger strings may be handled using the
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Postgres Large Object interface.
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</para>
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</sect2>
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<sect2>
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<title>Integer Constants</title>
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<para>
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<firstterm>Integer constants</firstterm>
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in SQL are collection of ASCII digits with no decimal point. Legal
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values range from -2147483648 to +2147483647. This will vary
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depending on the operating system and host machine.
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</para>
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<para>
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Note that larger integers can be specified for <type>int8</type>
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by using <acronym>SQL92</acronym> string notation or
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<productname>Postgres</productname> type notation:
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<programlisting>
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int8 '4000000000' -- string style
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'4000000000'::int8 -- Postgres (historical) style
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</programlisting>
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</para>
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</sect2>
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<sect2>
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<title>Floating Point Constants</title>
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<para>
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<firstterm>Floating point constants</firstterm>
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consist of an integer part, a decimal point, and a fraction part or
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scientific notation of the following format:
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<synopsis>
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{<replaceable>dig</replaceable>}.{<replaceable>dig</replaceable>} [e [+-] {<replaceable>dig</replaceable>}]
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</synopsis>
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where <replaceable>dig</replaceable> is one or more digits.
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You must include at least one <replaceable>dig</replaceable> after the
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period and after the [+-] if you use those options. An exponent with
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a missing mantissa has a mantissa of 1 inserted. There may be no
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extra characters embedded in the string.
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</para>
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<para>
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Floating point constaints are of type
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<type>float8</type>. <type>float4</type> can be specified
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explicitly by using <acronym>SQL92</acronym> string notation or
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<productname>Postgres</productname> type notation:
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<programlisting>
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float4 '1.23' -- string style
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'1.23'::float4 -- Postgres (historical) style
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</programlisting>
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</para>
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</sect2>
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<sect2>
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<title>Constants of Postgres User-Defined Types</title>
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<para>
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A constant of an
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<emphasis>arbitrary</emphasis>
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type can be entered using the notations:
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<synopsis>
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<replaceable>type</replaceable> '<replaceable>string</replaceable>'
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'<replaceable>string</replaceable>'::<replaceable>type</replaceable>
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CAST '<replaceable>string</replaceable>' AS <replaceable>type</replaceable>
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</synopsis>
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The value inside the string is passed to the input
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conversion routine for the type called
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<replaceable>type</replaceable>. The result is a
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constant of the indicated type. The explicit typecast may be omitted
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if there is no ambiguity as to the type the constant must be, in which
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case it is automatically coerced.
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</para>
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</sect2>
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<sect2>
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<title>Array constants</title>
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<para>
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<firstterm>Array constants</firstterm>
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are arrays of any Postgres type, including other arrays, string
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constants, etc. The general format of an array constant is the
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following:
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<synopsis>
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{<replaceable>val1</replaceable><replaceable>delim</replaceable><replaceable>val2</replaceable><replaceable>delim</replaceable>}
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</synopsis>
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where <replaceable>delim</replaceable>
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is the delimiter for the type stored in the <literal>pg_type</literal> class.
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(For built-in types, this is the comma character (","). An
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example of an array constant is
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<programlisting>
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{{1,2,3},{4,5,6},{7,8,9}}
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</programlisting>
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This constant is a two-dimensional, 3 by 3 array consisting of three
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sub-arrays of integers.
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</para>
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<para>
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Individual array elements can and should be placed between quotation
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marks whenever possible to avoid ambiguity problems with respect to
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leading white space.
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</para>
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</sect2>
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</sect1>
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<sect1>
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<title>Fields and Columns</title>
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<sect2>
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|
<title>Fields</title>
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<para>
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A <firstterm>field</firstterm>
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|
is either an attribute of a given class or one of the following:
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<variablelist>
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<varlistentry>
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<term>oid</term>
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<listitem>
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<para>
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stands for the unique identifier of an instance which is added by
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Postgres to all instances automatically. Oids are not reused and are 32
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bit quantities.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term>xmin</term>
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<listitem>
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<para>
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The identity of the inserting transaction.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term>xmax</term>
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<listitem>
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<para>
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The identity of the deleting transaction.
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</para>
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</listitem>
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</varlistentry>
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|
<varlistentry>
|
|
<term>cmin</term>
|
|
<listitem>
|
|
<para>
|
|
The command identifier within the transaction.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term>cmax</term>
|
|
<listitem>
|
|
<para>
|
|
The identity of the deleting command.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
</variablelist>
|
|
</para>
|
|
|
|
<para>
|
|
For further information on these fields consult
|
|
<xref linkend="STON87a" endterm="STON87a">.
|
|
Times are represented internally as instances of the
|
|
<literal>abstime</literal>
|
|
data type. Transaction and command identifiers are 32 bit quantities.
|
|
Transactions are assigned sequentially starting at 512.
|
|
</para>
|
|
</sect2>
|
|
|
|
<sect2>
|
|
<title>Columns</title>
|
|
|
|
<para>
|
|
A <firstterm>column</firstterm> is a construct of the form:
|
|
|
|
<synopsis>
|
|
<replaceable>instance</replaceable>{.<replaceable>composite_field</replaceable>}.<replaceable>field</replaceable> `['<replaceable>number</replaceable>`]'
|
|
</synopsis>
|
|
|
|
<replaceable>instance</replaceable>
|
|
identifies a particular class and can be thought of as standing for
|
|
the instances of that class. An instance variable is either a class
|
|
name, a surrogate for a class defined by means of a FROM clause,
|
|
or the keyword NEW or CURRENT.
|
|
NEW and CURRENT can only appear in the action portion of a rule, while
|
|
other instance variables can be used in any SQL statement.
|
|
<replaceable>composite_field</replaceable>
|
|
is a field of of one of the Postgres composite types,
|
|
while successive composite fields address attributes in the
|
|
class(s) to which the composite field evaluates. Lastly,
|
|
<replaceable>field</replaceable>
|
|
is a normal (base type) field in the class(s) last addressed. If
|
|
<replaceable>field</replaceable>
|
|
is of type <literal>array</literal>,
|
|
then the optional <replaceable>number</replaceable>
|
|
designator indicates a specific element in the array. If no number is
|
|
indicated, then all array elements are returned.
|
|
</para>
|
|
</sect2>
|
|
</sect1>
|
|
|
|
<sect1>
|
|
<title>Operators</title>
|
|
|
|
<para>
|
|
Any built-in system, or user-defined operator may be used in SQL.
|
|
For the list of built-in and system operators consult
|
|
<xref linkend="operators" endterm="operators-title">.
|
|
For a list of user-defined operators consult your system administrator
|
|
or run a query on the <literal>pg_operator</literal> class.
|
|
Parentheses may be used for arbitrary grouping of operators in expressions.
|
|
</para>
|
|
</sect1>
|
|
|
|
<sect1>
|
|
<title>Expressions</title>
|
|
|
|
<para>
|
|
<acronym>SQL92</acronym> allows <firstterm>expressions</firstterm>
|
|
to transform data in tables. Expressions may contain operators
|
|
(see <xref linkend="operators" endterm="operators-title">
|
|
for more details) and functions
|
|
(<xref linkend="functions" endterm="functions-title"> has
|
|
more information).
|
|
</para>
|
|
|
|
<para>
|
|
An expression is one of the following:
|
|
|
|
<simplelist>
|
|
<member>( a_expr )</member>
|
|
<member>constant</member>
|
|
<member>attribute</member>
|
|
<member><replaceable>a_expr</replaceable> <replaceable>binary_operator</replaceable> <replaceable>a_expr</replaceable></member>
|
|
<member><replaceable>a_expr</replaceable> <replaceable>right_unary_operator</replaceable></member>
|
|
<member><replaceable>left_unary_operator</replaceable> <replaceable>a_expr</replaceable></member>
|
|
<member>parameter</member>
|
|
<member>functional expressions</member>
|
|
<member>aggregate expressions</member>
|
|
</simplelist>
|
|
</para>
|
|
|
|
<para>
|
|
We have already discussed constants and attributes. The two kinds of
|
|
operator expressions indicate respectively binary and left_unary
|
|
expressions. The following sections discuss the remaining options.
|
|
</para>
|
|
|
|
<sect2>
|
|
<title>Parameters</title>
|
|
|
|
<para>
|
|
A <firstterm>parameter</firstterm>
|
|
is used to indicate a parameter in a SQL function. Typically this
|
|
is used in SQL function definition statement. The form of a
|
|
parameter is:
|
|
|
|
<synopsis>
|
|
$<replaceable class="parameter">number</replaceable>
|
|
</synopsis>
|
|
</para>
|
|
|
|
<para>
|
|
For example, consider the definition of a function,
|
|
<function>dept</function>, as
|
|
|
|
<programlisting>
|
|
CREATE FUNCTION dept (name)
|
|
RETURNS dept
|
|
AS 'select * from
|
|
dept where name=$1'
|
|
LANGUAGE 'sql';
|
|
</programlisting>
|
|
</para>
|
|
</sect2>
|
|
|
|
<sect2>
|
|
<title>Functional Expressions</title>
|
|
|
|
<para>
|
|
A <firstterm>functional expression</firstterm>
|
|
is the name of a legal SQL function, followed by its argument list
|
|
enclosed in parentheses:
|
|
|
|
<synopsis>
|
|
<replaceable>function</replaceable> (<replaceable>a_expr</replaceable> [, <replaceable>a_expr</replaceable> )
|
|
</synopsis>
|
|
</para>
|
|
|
|
<para>
|
|
For example, the following computes the square root of an employee
|
|
salary:
|
|
|
|
<programlisting>
|
|
sqrt(emp.salary)
|
|
</programlisting>
|
|
</para>
|
|
</sect2>
|
|
|
|
<sect2>
|
|
<title>Aggregate Expression</title>
|
|
|
|
<para>
|
|
An <firstterm>aggregate expression</firstterm>
|
|
represents a simple aggregate (i.e., one that computes a single value)
|
|
or an aggregate function (i.e., one that computes a set of values).
|
|
The syntax is the following:
|
|
|
|
<synopsis>
|
|
<replaceable>aggregate_name</replaceable> (<replaceable>attribute</replaceable>)
|
|
</synopsis>
|
|
|
|
where <replaceable>aggregate_name</replaceable>
|
|
must be a previously defined aggregate.
|
|
</para>
|
|
</sect2>
|
|
|
|
<sect2>
|
|
<title>Target List</title>
|
|
|
|
<para>
|
|
A <firstterm>target list</firstterm>
|
|
is a parenthesized, comma-separated list of one or more elements, each
|
|
of which must be of the form:
|
|
|
|
<synopsis>
|
|
<replaceable>a_expr</replaceable> [ AS <replaceable>result_attname</replaceable> ]
|
|
</synopsis>
|
|
|
|
where <replaceable>result_attname</replaceable>
|
|
is the name of the attribute to be created (or an
|
|
already existing attribute name in the case of update statements.) If
|
|
<replaceable>result_attname</replaceable>
|
|
is not present, then
|
|
<replaceable>a_expr</replaceable>
|
|
must contain only one attribute name which is assumed to be the name
|
|
of the result field. In <productname>Postgres</productname>
|
|
default naming is only used if
|
|
<replaceable>a_expr</replaceable>
|
|
is an attribute.
|
|
</para>
|
|
</sect2>
|
|
|
|
<sect2>
|
|
<title>Qualification</title>
|
|
|
|
<para>
|
|
A <firstterm>qualification</firstterm>
|
|
consists of any number of clauses connected by the logical operators:
|
|
|
|
<simplelist>
|
|
<member>NOT</member>
|
|
<member>AND</member>
|
|
<member>OR</member>
|
|
</simplelist>
|
|
|
|
A clause is an <replaceable>a_expr</replaceable>
|
|
that evaluates to a <literal>boolean</literal> over a set of instances.
|
|
</para>
|
|
</sect2>
|
|
|
|
<sect2>
|
|
<title>From List</title>
|
|
|
|
<para>
|
|
The <firstterm>from list</firstterm>
|
|
is a comma-separated list of <firstterm>from expressions</firstterm>.
|
|
Each "from expression" is of the form:
|
|
|
|
<synopsis>
|
|
[ <replaceable>class_reference</replaceable> ] <replaceable>instance_variable</replaceable>
|
|
{, [ <replaceable>class_ref</replaceable> ] <replaceable>instance_variable</replaceable>... }
|
|
</synopsis>
|
|
|
|
where <replaceable>class_reference</replaceable>
|
|
is of the form
|
|
|
|
<synopsis>
|
|
<replaceable>class_name</replaceable> [ * ]
|
|
</synopsis>
|
|
|
|
The "from expression"
|
|
defines one or more instance variables to range over the class
|
|
indicated in <replaceable>class_reference</replaceable>.
|
|
One can also request
|
|
the instance variable to range over all classes that are beneath the
|
|
indicated class in the inheritance hierarchy by postpending the
|
|
designator asterisk ("*").
|
|
</para>
|
|
</sect2>
|
|
</sect1>
|
|
</chapter>
|
|
|
|
<!-- Keep this comment at the end of the file
|
|
Local variables:
|
|
mode: sgml
|
|
sgml-omittag:nil
|
|
sgml-shorttag:t
|
|
sgml-minimize-attributes:nil
|
|
sgml-always-quote-attributes:t
|
|
sgml-indent-step:1
|
|
sgml-indent-data:t
|
|
sgml-parent-document:nil
|
|
sgml-default-dtd-file:"./reference.ced"
|
|
sgml-exposed-tags:nil
|
|
sgml-local-catalogs:"/usr/lib/sgml/CATALOG"
|
|
sgml-local-ecat-files:nil
|
|
End:
|
|
-->
|