I saw a SO post that says you can search using regex or an actual literal text on it to search multiline texts. But what if you want to (quickly) search two or three of words within a specified lines of text content?
For example, what if you want to search for multiline text area that contains "ruby" and "regex" (assuming you want to know where you took a note on your txt (or markdown or rich text format) file. you may want to search for "how to use regex in ruby" or "the ruby regex tutorial", right? )
Now you can use a simple (but redundant) regex like ruby(.*\n)+regex|regex(.*\n)+ruby. But to me it doesn't look beautiful. For three or more words, this kind of regex workaround increases its redundancy exponentially also, not good.
So is there a smarter way to do this? Thanks.
I'm searching for the function named "init"; along with init, I also get things like:
"function g = compute_gradient()"
where the substring characters aren't consecutive. Most of the time, it makes the whole search useless (faster to use a simple string search).
How do I fix that?
By the way, is this a bug? If not, what's the idea of such a search? I could understand looking for separate (by space) words; I don't get a search by separate letters.
As far as I can tell "Field position limit" in sphinx only allows you to force search to the first N characters in a document? Is there anyway to use it to force search AFTER the first N characters instead?
The quick brown fox jumped over the lazy dog and he was crazy as a fox and just as fast
Fox[20]
will find the first fox and not the second.
What I am looking for is something like
Fox[50] that won't start search until char 50 ("and he was crazy as a fox and just as fast")
Well you could say
"bla bla" #field[50] -"bla bla"
But you have the old problem of it also exlcuding items with it after as well as before.
Otherwise think you will have to look at ranking expressions, there is min_hit_pos which can use. Would have to use the ranking expression to change the ranking calculation, and then 'post filter' based on the weight. Can use the weight in WHERE, via virtual attributes.
(this wont work either, see comments!)
Is there an unicode symbol for "n/a"? There are some fractions like ½, but a n/a symbol seems to be missing.
If there is none, what would be the most appropriate unicode symbol to use for n/a in a website (which should be contained in common fonts, to avoid needing a webfont)?
Looking at the Unicode code charts, I do not see a single N/A symbol. I do, however, see ⁿ (U+207F) and ₐ (U+2090), which you could separate with / (U+002F) eg: ⁿ/ₐ, or ̷ (U+0337), eg: ⁿ̷ₐ, or ̸ (U+0338), eg: ⁿ̸ₐ. Probably not what you are hoping for, though. And I don't know if "common" fonts implement them, either.
For future reference, the fastest way I know to answer questions like the OP's when I have them myself is to go to unicodelookup.com, because of the way it works: there's a search bar at the top, and you just type a string and it will return any and all unicode characters containing that string (this is also a great way to discover new and useful symbols). So in the OP's case, he could proceed like this:
first try entering "not" (without the quotes) in the search field
visually scan through the results... doing so would not reveal a "not
applicable" character in this case
try again but this time entering "applic" in the search field
again, doing so would not turn up anything along the lines of what he's
looking for
At that point he would be reasonably confident the current Unicode standard does not have a "n/a" symbol.
If you use Firefox you can define a keyword like "uni" to search that site from the URL bar, meaning any time the browser is open and regardless of what page or site is currently showing, you could do this:
hit [F6]... this moves the cursor to the URL bar at the top
type something like "uni applic" and hit [Enter]... this brings up the
unicodelookup.com website with the search results for "applic" already
showing
For the above to work you would need to define your keyword ("uni" or wtv you prefer) to point to location http://unicodelookup.com/#%s.
There's a Negative Acknowlege icon...
␕ symbol for negative acknowledge 022025 9237 0x2415 ␕
Found by searching negative on the Unicode Lookup site.
I'm not a fan, and for my purposes have just gone with __N/A__ (Markdown..)
I see lots of answers going head-on at the "Not Applicable" abbreviation, without exploring what a symbol is. A quick search for the equivalent phrase "out of scope" brings up a couple of variations on the No symbol: ⃠ – this seems to fit the bill (and since I was looking for a way to represent inapplicability, I'll be using it in my technical document).
Per the Wikipedia article, the Unicode codepoint U+20E0 is a combining character, so it is superimposed on the preceding character; e.g. ! ⃠ overlays an exclamation point. To get it to appear isolated, use a non-breaking space
If you don't want to bother with the combining symbol, the article mentions there's also an emoji U+1F6AB 🚫 but it's typically going to be colored red, or won't render!
There's actually a single character that could be repurposed for this: the "Square Na" character ㎁ (U+3381), which is used to represent the nanoampere in fullwidth (CJK) scripts.
What about the "SYMBOL FOR NULL" ␀ (U+2400)?
I have an app that utilizes hashtags to help tag posts. I am trying to have a more detailed search.
Lets say one of the records I'm searching is:
The #bird flew very far.
When I search for "flew", "fle", or "#bird", it should return the record.
However, when I search "#bir", it should NOT return the sentence because the whole the tag being searched for doesn't match.
I'm also not sure if "bird" should even return the sentence. I'd be interested how to do that though as well.
Right now, I have a very basic search:
SELECT "posts".* FROM "posts" WHERE (body LIKE '%search%')
Any ideas?
You could do this with LIKE but it would be rather hideous, regexes will serve you better here. If you want to ignore the hashes then a simple search like this will do the trick:
WHERE body ~ E'\\mbird\M''
That would find 'The bird flew very far.' and 'The #bird flew very far.'. You'd want to strip off any #s before search though as this:
WHERE body ~ E'\\m#bird\M''
wouldn't find either of those results due to the nature of \m and \M.
If you don't want to ignore #s in body then you'd have to expand and modify the \m and \M shortcuts yourself with something like this:
WHERE body ~ E'(^|[^\\w#])#bird($|[^\\w#])'
-- search term goes here^^^^^
Using E'(^|[^\\w#])#bird($|[^\\w#])' would find 'The #bird flew very far.' but not 'The bird flew very far.' whereas E'(^|[^\\w#])bird($|[^\\w#])' would find 'The bird flew very far.' but not 'The #bird flew very far.'. You might also want to look at \A instead of ^ and \Z instead of $ as there are subtle differences but I think $ and ^ would be what you want.
You should keep in mind that none of these regex searches (or your LIKE search for that matter) will uses indexes so you're setting yourself up for lots of table scans and performance problems unless you can restrict the searches using something that will use an index. You might want to look at a full-text search solution instead.
It might help to parse the hash tags out of the text and store them in an array in a separate column called say hashtags when the articles are inserted/updated. Remove them from the article body before feeding it into to_tsvector and store the tsvector in a column of the table. Then use:
WHERE body_tsvector ## to_tsquery('search') OR 'search' IN hashtags
You could use a trigger on the table to maintain the hashtags column and the body_tsvector stripped of hash tags, so that the application doesn't have to do the work. Parse them out of the text when entries are INSERTed or UPDATEd.