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From Bryan Pendleton <bpendleton.de...@gmail.com>
Subject Re: What should the "Graphical Query Explainer" shows?
Date Sat, 29 May 2010 14:29:28 GMT
On 05/28/2010 10:27 PM, Nirmal Fernando wrote:
> Hi Again,
>
>> Where can I get the values for the "node type" and "pages visited",
>> are they in the SYSXPLAIN tables (I didn't notice these there)?
>>
>
> Pages visited is there in the SYSXPLAIN_SCAN_PROPS system table as
> NO_VISITED_PAGES, sorry about that.
>
> But what you meant by "node type" is not clear to me (Is it STMT_TYPE?) .

Hi Nirmal,

No, I meant OP_IDENTIFIER in SYSXPLAIN_RESULTSETS
http://db.apache.org/derby/docs/10.6/ref/rrefsysxplain_resultsets.html

STMT_TYPE is usually SELECT, althought it can also be INSERT, UPDATE, etc.

The information from SYSPLAIN_STATEMENTS, such as STMT_TYPE, STMT_TEXT,
and so forth (described here:
http://db.apache.org/derby/docs/10.6/ref/rrefsysxplain_statements.html)
is useful information, but when displaying an XML query plan in a browser
I'd expect to see this information perhaps in the title of the page,
or as a top level header.

Perhaps the beginning of the HTML-formatted page that is produced by
running the stylesheet over the XML-formatted query plan might look
something like:

<html>
<head>
<title>Visualization of statement STMT_ID</title>
</head>
<body>
<h1>Visualization of STMT_TYPE statement STMT_ID</h1>
<p><b>Statement Text:</b>STMT_TEXT</p>
...
</body>
</html>

Where the upper case tokens in the above mock-up are replaced by the actual
values from the SYSXPLAIN_STATEMENTS table.

thanks,

bryan




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