This question about Using an extension: Answered

EXTRACT keeps grabbing my header line

I'm getting a weird behavior out of EXTRACT. The short of it is if I have a heading on my table, it always seems to grab the heading instead of the first matching value.

The long version is this: I've been looking for a way to grep rows from a table based on a query and found EXTRACT as a way to do it. I don't know whether there are any other ways that work.

I have a table of people, where the first column is their name, the second is their building and the third is their room. That table is in a topic by itself.

I needed another topic that could, given a query string with the room number, give me the names of the people in that room. I am using it with an image map of the office floor plan.

As an aside, I tried using SEARCH as a starting point, but I couldn't figure out how to do a lookup.
<pre>%SEARCH{"%ROOM%" topic="PeopleTable" format="   * $Name" multiple="on" }%</pre>
This syntax doesn't work, but I do get the right number of rows; I just don't know how to query for the column value.

What does mostly work is
<pre>%EXTRACT{topic="PeopleTable" expand="off" 
  pattern="\|\s*(.*?)\s*\|\s*(.*?)\s*\|\s*(%ROOM%)\s*\|" 
  format="   * $1$n"}%</pre>

If I have no heading, it works perfectly.

The Table:
Name Building Room
Blow, Joe ABA 3103
Blow, Moe ABA 3103
Flow, Joe ABA 3113
Blow, Zoe ABA 3113

With my search with room=3103, I got
  • Name
  • Blow, Moe
If I use skip=1, i just get
  • Blow, Moe
If I get rid of the table heading, I get
  • Blow, Joe
  • Blow, Moe
-- MatthewKoundakjian - 27 Oct 2010

OH NO, I'm wrong. I am always getting the first row in my results.

With my search the table without a heading with room=3103, I get
  • Blow, Joe
  • Blow, Moe
With my search the table without a heading with room=3113, I get
  • Blow, Joe
  • Blow, Zoe
-- MatthewKoundakjian - 27 Oct 2010

I found something that works, though I can't figure out why the previous does not. The regex seems to behave just fine.


<!--
Interactive lookup

   * Set ROOM = %URLPARAM{"room" default="3103"}%
-->
%EXTRACT{topic="%TOPIC%" expand="off" 
 pattern="^\s*\|([^\|]+)\|([^\|]+)\|\s*(%ROOM%)\s*\|"
 format="   * $1$n" 
}%


Test cases: The result:
  • Blow, Joe
  • Blow, Moe

I'm considering this one answered.

-- MatthewKoundakjian - 05 Nov 2010

QuestionForm edit

Subject Using an extension
Extension FilterPlugin
Version Foswiki 1.1.0
Status Answered
Topic revision: r2 - 05 Nov 2010, MatthewKoundakjian
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