Обсуждение: Indexing for Expression type data using GIST

<div style="text-align: left;">Hi All,<br /><br />I am trying to implement indexing mechanism for the Expression type
datausing GIST. For that purpose I need to store some extra information in the Meta-Data of the GIST Index.<br />The
informationis entered when the index is created on the table. Can any body give me some suggestion how to do that. I'll
bereally grateful.<br /><br />Thanks in advance<br /><br />Salman<br /></div><br /><hr />Test your Star IQ <a
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On Thu, Mar 27, 2008 at 02:03:09PM -0500, Wizard Shah wrote:
> Hi All,
>
> I am trying to implement indexing mechanism for the Expression type
> data using GIST. For that purpose I need to store some extra
> information in the Meta-Data of the GIST Index.

There is no real provision for this but, depending on what it is there
may be other options. For example perhaps you can use the typmod or
something like that.

> The information is entered when the index is created on the table.
> Can any body give me some suggestion how to do that. I'll be really
> grateful.

If you provide some more information about what the information
represents we might be able to give you a better idea.

Have a nice day,
--
Martijn van Oosterhout   <kleptog@svana.org>   http://svana.org/kleptog/
> Please line up in a tree and maintain the heap invariant while
> boarding. Thank you for flying nlogn airlines.

<div style="text-align: left;">Hi, <br /><br />The information is a simple structure with a string and integer. It
basicallyrepresents what attributes of the expression are going to be part of the index<br /><br />struct
ExpIndexInfo<br/></div>{<br />    int count;<br />    char* ExpIndex;<br />};<br /><br />e.g we have an expression data
like "price > 1300 AND color = blue AND mileage > 20000" and the index will include only the price and mileage
attributes.The string "ExpIndex" will contain the attributes to be indexed (price and mileage) and  integer "count"
maintainsthe max number of attributes to be indexed on the expression. This is all to be specified at the index
creationtime and stored in the Meta-Data to be changed or retrieved later<br /><br />Regards<br /><br />Salman<br /><br
/><br/><br /><hr id="stopSpelling" />> Date: Thu, 27 Mar 2008 20:34:04 +0100<br />> From: kleptog@svana.org<br
/>>To: wizardshah@hotmail.com<br />> CC: pgsql-hackers@postgresql.org<br />> Subject: Re: [HACKERS] Indexing
forExpression type data using GIST<br />> <br />> On Thu, Mar 27, 2008 at 02:03:09PM -0500, Wizard Shah wrote:<br
/>>> Hi All,<br />> > <br />> > I am trying to implement indexing mechanism for the Expression
type<br/>> > data using GIST. For that purpose I need to store some extra<br />> > information in the
Meta-Dataof the GIST Index.<br />> <br />> There is no real provision for this but, depending on what it is
there<br/>> may be other options. For example perhaps you can use the typmod or<br />> something like that.<br
/>><br />> > The information is entered when the index is created on the table.<br />> > Can any body
giveme some suggestion how to do that. I'll be really<br />> > grateful.<br />> <br />> If you provide some
moreinformation about what the information<br />> represents we might be able to give you a better idea.<br />>
<br/>> Have a nice day,<br />> -- <br />> Martijn van Oosterhout <kleptog@svana.org>
http://svana.org/kleptog/<br/>> > Please line up in a tree and maintain the heap invariant while <br />> >
boarding.Thank you for flying nlogn airlines.<br /><br /><hr />How well do you know your celebrity gossip? <a
href="http://originals.msn.com/thebigdebate?ocid=T002MSN03N0707A"target="_new">Talk celebrity smackdowns here.</a>