Skip to content

P
Postgres FD Implementation
Commit 352a56ba authored by Tom Lane's avatar Tom Lane
Browse files
Options

Allow assignment to array elements not contiguous with those already 

present; intervening positions are filled with nulls.  This behavior
is required by SQL99 but was not implementable before 8.2 due to lack
of support for nulls in arrays.  I have only made it work for the
one-dimensional case, which is all that SQL99 requires.  It seems quite
complex to get it right in higher dimensions, and since we never allowed
extension at all in higher dimensions, I think that must count as a
future feature addition not a bug fix.
parent 673a573d
Expand all Hide whitespace changes
Inline Side-by-side
Showing with 267 additions and 91 deletions
doc/src/sgml/array.sgml
View file @ 352a56ba
<!-- $PostgreSQL: pgsql/doc/src/sgml/array.sgml,v 1.51 2006/05/09 23:12:54 momjian Exp $ -->
<!-- $PostgreSQL: pgsql/doc/src/sgml/array.sgml,v 1.52 2006/09/29 21:22:21 tgl Exp $ -->
<sect1 id="arrays">
<title>Arrays</title>
......@@ -350,11 +350,12 @@ UPDATE sal_emp SET pay_by_quarter[1:2] = '{27000,27000}'
</para>
<para>
A stored array value 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. For example, if array
<literal>myarray</> currently has 4 elements, it will have five
elements after an update that assigns to <literal>myarray[5]</>.
A stored array value can be enlarged by assigning to element(s) not already
present. Any positions between those previously present and the newly
assigned element(s) will be filled with nulls. For example, if array
<literal>myarray</> currently has 4 elements, it will have six
elements after an update that assigns to <literal>myarray[6]</>,
and <literal>myarray[5]</> will contain a null.
Currently, enlargement in this fashion is only allowed for one-dimensional
arrays, not multidimensional arrays.
</para>
......
src/backend/utils/adt/arrayfuncs.c
View file @ 352a56ba
This diff is collapsed.
src/test/regress/expected/arrays.out
View file @ 352a56ba
......@@ -143,6 +143,116 @@ SELECT a,b,c FROM arrtest;
[4:4]={NULL} | {3,4} | {foo,new_word}
(3 rows)
--
-- test array extension
--
CREATE TEMP TABLE arrtest1 (i int[], t text[]);
insert into arrtest1 values(array[1,2,null,4], array['one','two',null,'four']);
select * from arrtest1;
i | t
--------------+---------------------
{1,2,NULL,4} | {one,two,NULL,four}
(1 row)
update arrtest1 set i[2] = 22, t[2] = 'twenty-two';
select * from arrtest1;
i | t
---------------+----------------------------
{1,22,NULL,4} | {one,twenty-two,NULL,four}
(1 row)
update arrtest1 set i[5] = 5, t[5] = 'five';
select * from arrtest1;
i | t
-----------------+---------------------------------
{1,22,NULL,4,5} | {one,twenty-two,NULL,four,five}
(1 row)
update arrtest1 set i[8] = 8, t[8] = 'eight';
select * from arrtest1;
i | t
-----------------------------+-------------------------------------------------
{1,22,NULL,4,5,NULL,NULL,8} | {one,twenty-two,NULL,four,five,NULL,NULL,eight}
(1 row)
update arrtest1 set i[0] = 0, t[0] = 'zero';
select * from arrtest1;
i | t
-------------------------------------+------------------------------------------------------------
[0:8]={0,1,22,NULL,4,5,NULL,NULL,8} | [0:8]={zero,one,twenty-two,NULL,four,five,NULL,NULL,eight}
(1 row)
update arrtest1 set i[-3] = -3, t[-3] = 'minus-three';
select * from arrtest1;
i | t
---------------------------------------------------+-----------------------------------------------------------------------------------
[-3:8]={-3,NULL,NULL,0,1,22,NULL,4,5,NULL,NULL,8} | [-3:8]={minus-three,NULL,NULL,zero,one,twenty-two,NULL,four,five,NULL,NULL,eight}
(1 row)
update arrtest1 set i[0:2] = array[10,11,12], t[0:2] = array['ten','eleven','twelve'];
select * from arrtest1;
i | t
-----------------------------------------------------+---------------------------------------------------------------------------------
[-3:8]={-3,NULL,NULL,10,11,12,NULL,4,5,NULL,NULL,8} | [-3:8]={minus-three,NULL,NULL,ten,eleven,twelve,NULL,four,five,NULL,NULL,eight}
(1 row)
update arrtest1 set i[8:10] = array[18,null,20], t[8:10] = array['p18',null,'p20'];
select * from arrtest1;
i | t
---------------------------------------------------------------+-----------------------------------------------------------------------------------------
[-3:10]={-3,NULL,NULL,10,11,12,NULL,4,5,NULL,NULL,18,NULL,20} | [-3:10]={minus-three,NULL,NULL,ten,eleven,twelve,NULL,four,five,NULL,NULL,p18,NULL,p20}
(1 row)
update arrtest1 set i[11:12] = array[null,22], t[11:12] = array[null,'p22'];
select * from arrtest1;
i | t
-----------------------------------------------------------------------+--------------------------------------------------------------------------------------------------
[-3:12]={-3,NULL,NULL,10,11,12,NULL,4,5,NULL,NULL,18,NULL,20,NULL,22} | [-3:12]={minus-three,NULL,NULL,ten,eleven,twelve,NULL,four,five,NULL,NULL,p18,NULL,p20,NULL,p22}
(1 row)
update arrtest1 set i[15:16] = array[null,26], t[15:16] = array[null,'p26'];
select * from arrtest1;
i | t
-----------------------------------------------------------------------------------------+---------------------------------------------------------------------------------------------------------------------
[-3:16]={-3,NULL,NULL,10,11,12,NULL,4,5,NULL,NULL,18,NULL,20,NULL,22,NULL,NULL,NULL,26} | [-3:16]={minus-three,NULL,NULL,ten,eleven,twelve,NULL,four,five,NULL,NULL,p18,NULL,p20,NULL,p22,NULL,NULL,NULL,p26}
(1 row)
update arrtest1 set i[-5:-3] = array[-15,-14,-13], t[-5:-3] = array['m15','m14','m13'];
select * from arrtest1;
i | t
--------------------------------------------------------------------------------------------------+---------------------------------------------------------------------------------------------------------------------
[-5:16]={-15,-14,-13,NULL,NULL,10,11,12,NULL,4,5,NULL,NULL,18,NULL,20,NULL,22,NULL,NULL,NULL,26} | [-5:16]={m15,m14,m13,NULL,NULL,ten,eleven,twelve,NULL,four,five,NULL,NULL,p18,NULL,p20,NULL,p22,NULL,NULL,NULL,p26}
(1 row)
update arrtest1 set i[-7:-6] = array[-17,null], t[-7:-6] = array['m17',null];
select * from arrtest1;
i | t
-----------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------
[-7:16]={-17,NULL,-15,-14,-13,NULL,NULL,10,11,12,NULL,4,5,NULL,NULL,18,NULL,20,NULL,22,NULL,NULL,NULL,26} | [-7:16]={m17,NULL,m15,m14,m13,NULL,NULL,ten,eleven,twelve,NULL,four,five,NULL,NULL,p18,NULL,p20,NULL,p22,NULL,NULL,NULL,p26}
(1 row)
update arrtest1 set i[-12:-10] = array[-22,null,-20], t[-12:-10] = array['m22',null,'m20'];
select * from arrtest1;
i | t
-----------------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------
[-12:16]={-22,NULL,-20,NULL,NULL,-17,NULL,-15,-14,-13,NULL,NULL,10,11,12,NULL,4,5,NULL,NULL,18,NULL,20,NULL,22,NULL,NULL,NULL,26} | [-12:16]={m22,NULL,m20,NULL,NULL,m17,NULL,m15,m14,m13,NULL,NULL,ten,eleven,twelve,NULL,four,five,NULL,NULL,p18,NULL,p20,NULL,p22,NULL,NULL,NULL,p26}
(1 row)
delete from arrtest1;
insert into arrtest1 values(array[1,2,null,4], array['one','two',null,'four']);
select * from arrtest1;
i | t
--------------+---------------------
{1,2,NULL,4} | {one,two,NULL,four}
(1 row)
update arrtest1 set i[0:5] = array[0,1,2,null,4,5], t[0:5] = array['z','p1','p2',null,'p4','p5'];
select * from arrtest1;
i | t
------------------------+----------------------------
[0:5]={0,1,2,NULL,4,5} | [0:5]={z,p1,p2,NULL,p4,p5}
(1 row)
--
-- array expressions and operators
--
......
src/test/regress/sql/arrays.sql
View file @ 352a56ba
......@@ -90,6 +90,42 @@ SELECT a FROM arrtest WHERE a[2] IS NULL;
DELETE FROM arrtest WHERE a[2] IS NULL AND b IS NULL;
SELECT a,b,c FROM arrtest;
--
-- test array extension
--
CREATE TEMP TABLE arrtest1 (i int[], t text[]);
insert into arrtest1 values(array[1,2,null,4], array['one','two',null,'four']);
select * from arrtest1;
update arrtest1 set i[2] = 22, t[2] = 'twenty-two';
select * from arrtest1;
update arrtest1 set i[5] = 5, t[5] = 'five';
select * from arrtest1;
update arrtest1 set i[8] = 8, t[8] = 'eight';
select * from arrtest1;
update arrtest1 set i[0] = 0, t[0] = 'zero';
select * from arrtest1;
update arrtest1 set i[-3] = -3, t[-3] = 'minus-three';
select * from arrtest1;
update arrtest1 set i[0:2] = array[10,11,12], t[0:2] = array['ten','eleven','twelve'];
select * from arrtest1;
update arrtest1 set i[8:10] = array[18,null,20], t[8:10] = array['p18',null,'p20'];
select * from arrtest1;
update arrtest1 set i[11:12] = array[null,22], t[11:12] = array[null,'p22'];
select * from arrtest1;
update arrtest1 set i[15:16] = array[null,26], t[15:16] = array[null,'p26'];
select * from arrtest1;
update arrtest1 set i[-5:-3] = array[-15,-14,-13], t[-5:-3] = array['m15','m14','m13'];
select * from arrtest1;
update arrtest1 set i[-7:-6] = array[-17,null], t[-7:-6] = array['m17',null];
select * from arrtest1;
update arrtest1 set i[-12:-10] = array[-22,null,-20], t[-12:-10] = array['m22',null,'m20'];
select * from arrtest1;
delete from arrtest1;
insert into arrtest1 values(array[1,2,null,4], array['one','two',null,'four']);
select * from arrtest1;
update arrtest1 set i[0:5] = array[0,1,2,null,4,5], t[0:5] = array['z','p1','p2',null,'p4','p5'];
select * from arrtest1;
--
-- array expressions and operators
--
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment