Regular Expression Operator

[mandolyte]

I'm new to document databases and I wondered whether regular expression support would be useful. You could always do this on the client side, but a large result set could be slow (large amount of data being returned to client over network connection).

If the regex was implemented on the server side, wouldn't that be more efficient?

I'm enjoying tiedot, thanks!

[HouzuoGuo]

Hello!

I am very glad to hear that you like tiedot.

Did you mean using regular expression to filter certain attribute in query result? For example, matching /(good)|(average)/ in document's "grade".

[mandolyte]

Yes, or more complex: /[AF]/ in document's "grade". The high and low performers. Or again, to do wildcard searching,such as

• all names ending in the letter "n": /n$/
• all codes beginning with a letter and ending in a digit: /^[0-9].*[A-Z]$/

Since Go has a regexp package (http://golang.org/pkg/regexp/), I thought it would be pretty easy and would be nice addition the current eq, range, and set operations. In SQL I use wildcards a lot and noticed the absence in tiedot right away.

[HouzuoGuo]

Oh! I see.

In that case, I am afraid that index scan cannot help much at this stage, regex filter can be applied in collection scan (which is still quite fast).

[mandolyte]

So would it look something like this?

q='{"re": "Go|Clojure", "in": ["Title"]}'

to find every title with either "Go" or "Clojure" in the title.

Thanks for considering,
Cecil

[HouzuoGuo]

That sounds like a great idea, let's do it.

[HouzuoGuo]

Fixed in d76e5aa thanks to NoahShen

[mandolyte]

Great! Don't forget to update the docs to show how to use it!

On Thu, Nov 7, 2013 at 1:47 AM, Howard Guo notifications@github.com wrote:

Fixed in d76e5aahttps://github.com/HouzuoGuo/tiedot/commit/d76e5aa969b2e3cfb0a98cce9b77c077345741c9thanks to NoahShen

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Reply to this email directly or view it on GitHubhttps://github.com//issues/27#issuecomment-27941459
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[HouzuoGuo]

will do

[HouzuoGuo]

Completed 9a5026a