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Fix markup and license.

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Teodor Sigaev 2006-09-05 18:39:08 +00:00
parent 889ec4b998
commit febc10de2d
1 changed files with 14 additions and 9 deletions
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23
contrib/hstore/README.hstore
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@ -11,9 +11,8 @@ Authors
* Oleg Bartunov <oleg@sai.msu.su>, Moscow, Moscow University, Russia
* Teodor Sigaev <teodor@sigaev.ru>, Moscow, Delta-Soft Ltd.,Russia
License
Stable version, included into PostgreSQL distribution, released under BSD license. Development version, available from this site, released under the GNU General Public License, version 2 (June 1991).
LEGAL NOTICES: This module is released under BSD license (as PostgreSQL
itself)
Operations
@ -61,7 +60,8 @@ regression=# select 'a=>b, b=>1, c=>NULL'::hstore @ 'b=>1';
t
(1 row)
* hstore ~ hstore - contained operation, check if left operand is contained in right
* hstore ~ hstore - contained operation, check if left operand is contained
in right
Functions
@ -95,7 +95,8 @@ regression=# select svals('a=>1,b=>2');
1
2
* delete (hstore,text) - delete (key,value) from hstore if key matches argument.
* delete (hstore,text) - delete (key,value) from hstore if key matches
argument.
regression=# select delete('a=>1,b=>2','b');
delete
@ -110,14 +111,16 @@ regression=# select * from each('a=>1,b=>2');
a | 1
b | 2
* isexists (hstore,text) - returns 'true if key is exists in hstore and false otherwise.
* isexists (hstore,text) - returns 'true if key is exists in hstore and
false otherwise.
regression=# select isexists('a=>1','a');
isexists
----------
t
* isdefined (hstore,text) - returns true if key is exists in hstore and its value is not NULL.
* isdefined (hstore,text) - returns true if key is exists in hstore and
its value is not NULL.
regression=# select isdefined('a=>NULL','a');
isdefined
@ -148,7 +151,9 @@ update tt set h=delete(h,'k1');
* Statistics
hstore type, because of its intrinsic liberality, could contain a lot of different keys. Checking for valid keys is the task of application. Examples below demonstrate several techniques how to check keys statistics.
hstore type, because of its intrinsic liberality, could contain a lot of
different keys. Checking for valid keys is the task of application.
Examples below demonstrate several techniques how to check keys statistics.
o simple example
@ -172,4 +177,4 @@ select key, count(*) from (select (each(h)).key from testhstore) as stat group b
public | 194
title | 190
org | 189
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