diff options
Diffstat (limited to 'doc/src/sgml/syntax.sgml')
| -rw-r--r-- | doc/src/sgml/syntax.sgml | 64 |
1 files changed, 32 insertions, 32 deletions
diff --git a/doc/src/sgml/syntax.sgml b/doc/src/sgml/syntax.sgml index 744a13ef478..48bf5a4feb8 100644 --- a/doc/src/sgml/syntax.sgml +++ b/doc/src/sgml/syntax.sgml @@ -1,4 +1,4 @@ -<!-- $PostgreSQL: pgsql/doc/src/sgml/syntax.sgml,v 1.130 2009/02/04 21:30:41 alvherre Exp $ --> +<!-- $PostgreSQL: pgsql/doc/src/sgml/syntax.sgml,v 1.131 2009/04/27 16:27:36 momjian Exp $ --> <chapter id="sql-syntax"> <title>SQL Syntax</title> @@ -11,12 +11,12 @@ <para> This chapter describes the syntax of SQL. It forms the foundation for understanding the following chapters which will go into detail - about how the SQL commands are applied to define and modify data. + about how SQL commands are applied to define and modify data. </para> <para> We also advise users who are already familiar with SQL to read this - chapter carefully because there are several rules and concepts that + chapter carefully because it contains several rules and concepts that are implemented inconsistently among SQL databases or that are specific to <productname>PostgreSQL</productname>. </para> @@ -293,7 +293,7 @@ U&"d!0061t!+000061" UESCAPE '!' bounded by single quotes (<literal>'</literal>), for example <literal>'This is a string'</literal>. To include a single-quote character within a string constant, - write two adjacent single quotes, e.g. + write two adjacent single quotes, e.g., <literal>'Dianne''s horse'</literal>. Note that this is <emphasis>not</> the same as a double-quote character (<literal>"</>). <!-- font-lock sanity: " --> @@ -337,7 +337,7 @@ SELECT 'foo' 'bar'; string constants, which are an extension to the SQL standard. An escape string constant is specified by writing the letter <literal>E</literal> (upper or lower case) just before the opening single - quote, e.g. <literal>E'foo'</>. (When continuing an escape string + quote, e.g., <literal>E'foo'</>. (When continuing an escape string constant across lines, write <literal>E</> only before the first opening quote.) Within an escape string, a backslash character (<literal>\</>) begins a @@ -422,14 +422,14 @@ SELECT 'foo' 'bar'; <xref linkend="guc-standard-conforming-strings"> is <literal>off</>, then <productname>PostgreSQL</productname> recognizes backslash escapes in both regular and escape string constants. This is for backward - compatibility with the historical behavior, in which backslash escapes + compatibility with the historical behavior, where backslash escapes were always recognized. Although <varname>standard_conforming_strings</> currently defaults to <literal>off</>, the default will change to <literal>on</> in a future release for improved standards compliance. Applications are therefore encouraged to migrate away from using backslash escapes. If you need to use a backslash escape to represent a special character, write the - constant with an <literal>E</> to be sure it will be handled the same + string constant with an <literal>E</> to be sure it will be handled the same way in future releases. </para> @@ -442,7 +442,7 @@ SELECT 'foo' 'bar'; </caution> <para> - The character with the code zero cannot be in a string constant. + The zero-byte (null byte) character cannot be in a string constant. </para> </sect3> @@ -896,7 +896,7 @@ CAST ( '<replaceable>string</replaceable>' AS <replaceable>type</replaceable> ) </indexterm> <para> - A comment is an arbitrary sequence of characters beginning with + A comment is a sequence of characters beginning with double dashes and extending to the end of the line, e.g.: <programlisting> -- This is a standard SQL comment @@ -918,8 +918,8 @@ CAST ( '<replaceable>string</replaceable>' AS <replaceable>type</replaceable> ) </para> <para> - A comment is removed from the input stream before further syntax - analysis and is effectively replaced by whitespace. + Comment are removed from the input stream before further syntax + analysis and are effectively replaced by whitespace. </para> </sect2> @@ -1112,7 +1112,7 @@ SELECT 3 OPERATOR(pg_catalog.+) 4; </programlisting> the <literal>OPERATOR</> construct is taken to have the default precedence shown in <xref linkend="sql-precedence-table"> for <quote>any other</> operator. This is true no matter - which specific operator name appears inside <literal>OPERATOR()</>. + which specific operator appears inside <literal>OPERATOR()</>. </para> </sect2> </sect1> @@ -1154,80 +1154,80 @@ SELECT 3 OPERATOR(pg_catalog.+) 4; <itemizedlist> <listitem> <para> - A constant or literal value. + A constant or literal value </para> </listitem> <listitem> <para> - A column reference. + A column reference </para> </listitem> <listitem> <para> A positional parameter reference, in the body of a function definition - or prepared statement. + or prepared statement </para> </listitem> <listitem> <para> - A subscripted expression. + A subscripted expression </para> </listitem> <listitem> <para> - A field selection expression. + A field selection expression </para> </listitem> <listitem> <para> - An operator invocation. + An operator invocation </para> </listitem> <listitem> <para> - A function call. + A function call </para> </listitem> <listitem> <para> - An aggregate expression. + An aggregate expression </para> </listitem> <listitem> <para> - A window function call. + A window function call </para> </listitem> <listitem> <para> - A type cast. + A type cast </para> </listitem> <listitem> <para> - A scalar subquery. + A scalar subquery </para> </listitem> <listitem> <para> - An array constructor. + An array constructor </para> </listitem> <listitem> <para> - A row constructor. + A row constructor </para> </listitem> @@ -1264,7 +1264,7 @@ SELECT 3 OPERATOR(pg_catalog.+) 4; </indexterm> <para> - A column can be referenced in the form + A column can be referenced in the form: <synopsis> <replaceable>correlation</replaceable>.<replaceable>columnname</replaceable> </synopsis> @@ -1426,7 +1426,7 @@ $1.somecolumn where the <replaceable>operator</replaceable> token follows the syntax rules of <xref linkend="sql-syntax-operators">, or is one of the key words <token>AND</token>, <token>OR</token>, and - <token>NOT</token>, or is a qualified operator name in the form + <token>NOT</token>, or is a qualified operator name in the form: <synopsis> <literal>OPERATOR(</><replaceable>schema</><literal>.</><replaceable>operatorname</><literal>)</> </synopsis> @@ -1714,7 +1714,7 @@ CAST ( <replaceable>expression</replaceable> AS <replaceable>type</replaceable> casts that are marked <quote>OK to apply implicitly</> in the system catalogs. Other casts must be invoked with explicit casting syntax. This restriction is intended to prevent - surprising conversions from being applied silently. + surprising conversions from being silently applied. </para> <para> @@ -1730,7 +1730,7 @@ CAST ( <replaceable>expression</replaceable> AS <replaceable>type</replaceable> <literal>timestamp</> can only be used in this fashion if they are double-quoted, because of syntactic conflicts. Therefore, the use of the function-like cast syntax leads to inconsistencies and should - probably be avoided in new applications. + probably be avoided. </para> <note> @@ -1794,7 +1794,7 @@ SELECT name, (SELECT max(pop) FROM cities WHERE cities.state = states.name) <para> An array constructor is an expression that builds an - array value from values for its member elements. A simple array + array using values for its member elements. A simple array constructor consists of the key word <literal>ARRAY</literal>, a left square bracket <literal>[</>, a list of expressions (separated by commas) for the @@ -1925,8 +1925,8 @@ SELECT ARRAY(SELECT oid FROM pg_proc WHERE proname LIKE 'bytea%'); </indexterm> <para> - A row constructor is an expression that builds a row value (also - called a composite value) from values + A row constructor is an expression that builds a row (also + called a composite value) using values for its member fields. A row constructor consists of the key word <literal>ROW</literal>, a left parenthesis, zero or more expressions (separated by commas) for the row field values, and finally |