diff --git a/doc/src/sgml/advanced.sgml b/doc/src/sgml/advanced.sgml
index 7876eac4104451d477581ff0e2edd9057d1107d4..13cdf168634fe3d4570133f5f21418ddbdf28dd3 100644
--- a/doc/src/sgml/advanced.sgml
+++ b/doc/src/sgml/advanced.sgml
@@ -1,5 +1,5 @@
<!--
-$Header: /cvsroot/pgsql/doc/src/sgml/advanced.sgml,v 1.16 2000/09/29 20:21:33 petere Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/advanced.sgml,v 1.17 2000/12/18 23:39:37 tgl Exp $
-->
<chapter id="advanced">
@@ -178,7 +178,7 @@ CREATE TABLE SAL_EMP (
salary by quarter and a two-dimensional array of
<firstterm>text</firstterm>
(schedule), which represents the employee's weekly
- schedule. Now we do some <firstterm>INSERTS</firstterm>s;
+ schedule. Now we do some <firstterm>INSERT</firstterm>s;
note that when
appending to an array, we enclose the values within
braces and separate them by commas. If you know
@@ -239,8 +239,9 @@ SELECT SAL_EMP.pay_by_quarter[3] FROM SAL_EMP;
</para>
<para>
- We can also access arbitrary slices of an array, or
- subarrays. This query retrieves the first item on
+ We can also access arbitrary slices of an array (subarrays)
+ by specifying both lower and upper bounds for
+ each subscript. This query retrieves the first item on
Bill's schedule for the first two days of the week.
<programlisting>
diff --git a/doc/src/sgml/array.sgml b/doc/src/sgml/array.sgml
index 5947df26c7ac5e70a4e35e35d232dd04e9728096..427a3956cd3e065983fd922896c056dbdb27e306 100644
--- a/doc/src/sgml/array.sgml
+++ b/doc/src/sgml/array.sgml
@@ -1,3 +1,7 @@
+<!--
+$Header: /cvsroot/pgsql/doc/src/sgml/array.sgml,v 1.8 2000/12/18 23:39:37 tgl Exp $
+-->
+
<Chapter Id="arrays">
<Title>Arrays</Title>
@@ -30,7 +34,7 @@ CREATE TABLE sal_emp (
(pay_by_quarter), which represents the employee's
salary by quarter, and a two-dimensional array of <FirstTerm>text</FirstTerm>
(schedule), which represents the employee's weekly
- schedule. Now we do some <FirstTerm>INSERTS</FirstTerm>s; note that when
+ schedule. Now we do some <FirstTerm>INSERT</FirstTerm>s; note that when
appending to an array, we enclose the values within
braces and separate them by commas. If you know <FirstTerm>C</FirstTerm>,
this is not unlike the syntax for initializing structures.
@@ -82,9 +86,10 @@ SELECT pay_by_quarter[3] FROM sal_emp;
</Para>
<Para>
- We can also access arbitrary slices of an array, or
+ We can also access arbitrary rectangular slices of an array, or
subarrays. An array slice is denoted by writing
- "lower subscript : upper subscript" for one or more array
+ <replaceable>lower subscript</replaceable> <literal>:</literal>
+ <replaceable>upper subscript</replaceable> for one or more array
dimensions. This query retrieves the first item on
Bill's schedule for the first two days of the week:
@@ -103,7 +108,11 @@ SELECT schedule[1:2][1:1] FROM sal_emp WHERE name = 'Bill';
SELECT schedule[1:2][1] FROM sal_emp WHERE name = 'Bill';
</ProgramListing>
- with the same result.
+ with the same result. An array subscripting operation is taken to
+ represent an array slice if any of the subscripts are written in
+ the form <replaceable>lower</replaceable> <literal>:</literal>
+ <replaceable>upper</replaceable>. A lower bound of 1 is assumed
+ for any subscript where only one value is specified.
</Para>
<Para>
@@ -114,7 +123,7 @@ UPDATE sal_emp SET pay_by_quarter = '{25000,25000,27000,27000}'
WHERE name = 'Carol';
</ProgramListing>
- or updated at a single entry:
+ or updated at a single element:
<ProgramListing>
UPDATE sal_emp SET pay_by_quarter[4] = 15000
@@ -132,10 +141,11 @@ UPDATE sal_emp SET pay_by_quarter[1:2] = '{27000,27000}'
<Para>
An array can be enlarged by assigning to an element adjacent to
those already present, or by assigning to a slice that is adjacent
- to or overlaps the data already present. Currently, this is only
- allowed for one-dimensional arrays, not multidimensional arrays.
+ to or overlaps the data already present.
For example, if an array value currently has 4 elements, it will
have five elements after an update that assigns to array[5].
+ Currently, enlargement in this fashion is only
+ allowed for one-dimensional arrays, not multidimensional arrays.
</Para>
<Para>
@@ -160,4 +170,22 @@ CREATE TABLE tictactoe (
number of dimensions.
</Para>
+<Para>
+ The current dimensions of any array value can be retrieved with
+ the <function>array_dims</function> function:
+
+<ProgramListing>
+SELECT array_dims(schedule) FROM sal_emp WHERE name = 'Carol';
+
+ array_dims
+------------
+ [1:2][1:1]
+(1 row)
+</ProgramListing>
+
+ <function>array_dims</function> produces a <type>text</type> result,
+ which is convenient for people to read but perhaps not so convenient
+ for programs.
+</Para>
+
</Chapter>
diff --git a/doc/src/sgml/syntax.sgml b/doc/src/sgml/syntax.sgml
index 596f91f818af6ebd05265c56ad5a9f568d44cae2..ee249b684a3742e31b0c6293c8981e0a518a3a9d 100644
--- a/doc/src/sgml/syntax.sgml
+++ b/doc/src/sgml/syntax.sgml
@@ -1,5 +1,5 @@
<!--
-$Header: /cvsroot/pgsql/doc/src/sgml/syntax.sgml,v 1.28 2000/12/17 05:47:57 tgl Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/syntax.sgml,v 1.29 2000/12/18 23:39:37 tgl Exp $
-->
<chapter id="syntax">
@@ -555,12 +555,10 @@ CAST ( '<replaceable>string</replaceable>' AS <replaceable>type</replaceable> )
</para>
<para>
- Individual array elements can be placed between single-quote
- marks to avoid ambiguity problems with respect to leading white space.
- Without quote marks, the array-value parser will skip white space.
- Note that to write a quote mark inside a string literal that is to
- become an array value, you must double the quote mark as described
- previously.
+ Individual array elements can be placed between double-quote
+ marks (<literal>"</literal>) to avoid ambiguity problems with respect to
+ white space.
+ Without quote marks, the array-value parser will skip leading white space.
</para>
</sect2>
</sect1>