I have a PHP function that accepts a parameter called $letter and I want to set the default value of the parameter to a pattern which is "any number or any symbol". How can I do that?
This is my query by the way .
select ID from $wpdb->posts where post_title LIKE '".$letter."%
I tried posting at wordpress stackexchange and they told me to post it here as this is an SQL/general programming question that specific to wordpress.
Thank you! Replies much appreciated :)
In order to match just numbers or letters (I'm not sure exactly what you mean by symbols) you can use the RLIKE operator in MySQL:
SELECT ... WHERE post_title RLIKE '^[A-Za-z0-9]'
That means by default $letter would be [A-Za-z0-9] - this means all letters from a to z (both cases) and numbers from 0-9. If you need specific symbols you can add them to the list (but - has to be first or last, since otherwise it has a special meaning of range). The ^ character tells it to be at the beginning of the string. So you will need something like:
"select ID from $wpdb->posts where post_title RLIKE '^".$letter."%'"
Of course I have to warn you against SQL injection attacks if you build your query like this without sanitizing the input (making sure it doesn't have any ' (apostrophe) in it.
Edit
To match a title that starts with a number just use [0-9] - that means it will match one digit from 0 to 9
Related
Am trying to determine how one attempts to identify, in Snowflake SQL, if a product code begins with three letters.
Suggestions?
I did just try: LEFT(P0.PRODUCTCODE,3) NOT LIKE '[a-zA-Z]%' but it didn't work.
Thanks folks
You can use REGEXP_LIKE to return a boolean value indicating whether or not your string matched the pattern you're interested in.
In your case, something like REGEXP_LIKE(string_field_here, '[a-zA-Z]{3}.*')
Breaking down the regular expression pattern:
[a-zA-Z]: Only match letter characters, both upper and lowercase
{3}: Require three of those letters
.*: Allow any number of any characters after those three letters
Note: in many cases, you would need to specifically indicate the beginning/ending of the string in the pattern, but Snowflake's implementation handles that for you. From the docs:
The function implicitly anchors a pattern at both ends (i.e. ''
automatically becomes '^$', and 'ABC' automatically becomes '^ABC$').
To match any string starting with ABC, the pattern would be 'ABC.*'.
You can try running these examples:
SELECT REGEXP_LIKE('abc', '[a-zA-Z]{3}.*') AS _abc,
REGEXP_LIKE('123', '[a-zA-Z]{3}.*') AS _123,
REGEXP_LIKE('abc123', '[a-zA-Z]{3}.*') AS _abc123,
REGEXP_LIKE('123abc', '[a-zA-Z]{3}.*') AS _123abc
I'm looking to query a postgresql database full of strings, specifically for strings with the word 'LOVE' in - this means only this specific version of the word and nothing where love is the stem or has that sequence of characters inside another word. I've so far been using the SELECT * FROM songs WHERE title LIKE '%LOVE%';, which mostly returns the desired results.
However, it also returns results like CRIMSON AND CLOVER, LOVESTONED/I THINK SHE KNOWS (INTERLUDE), LOVER YOU SHOULD'VE COME OVER and TO BE LOVED, which I want to exclude as they are specifically the word 'LOVE'.
I know you can use SELECT * FROM songs WHERE title = 'LOVE';, but this will obviously miss any string that isn't exactly 'LOVE'. Is there an operation in postgresql that can return the results I need?
You can use a regular expression that looks for love either with a space before or after, or if the word is at the start or end of the string:
with songs (title) as (
values
('Crimson And Clover'),
('Love hurts'),
('Only love can tear us apart'),
('To be loved'),
('Tainted love')
)
select *
from songs
where title ~* '\mlove\M';
The ~* is the regex operator and uses case insensitive comparison. The \m and \M restrict the match to the beginning and end of a word.
returns:
title
---------------------------
Love hurts
Only love can tear us apart
Tainted love
Online example: http://rextester.com/EUTHKM33922
My task is to validate existing data in an MSSQL database. I've got some SQL experience, but not enough, apparently. We have a zip code field that must be either 5 or 9 digits (US zip). What we are finding in the zip field are embedded spaces and other oddities that will be prevented in the future. I've searched enough to find the references for LIKE that leave me with this "novice approach":
ZIP NOT LIKE '[0-9][0-9][0-9][0-9][0-9]'
AND ZIP NOT LIKE '[0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]'
Is this really what I must code? Is there nothing similar to...?
ZIP NOT LIKE '[\d]{5}' AND ZIP NOT LIKE '[\d]{9}'
I will loath validating longer fields! I suppose, ultimately, both code sequences will be equally efficient (or should be).
Thanks for your help
Unfortunately, LIKE is not regex-compatible so nothing of the sort \d. Although, combining a length function with a numeric function may provide an acceptable result:
WHERE ISNUMERIC(ZIP) <> 1 OR LEN(ZIP) NOT IN(5,9)
I would however not recommend it because it ISNUMERIC will return 1 for a +, - or valid currency symbol. Especially the minus sign may be prevalent in the data set, so I'd still favor your "novice" approach.
Another approach is to use:
ZIP NOT LIKE '%[^0-9]%' OR LEN(ZIP) NOT IN(5,9)
which will find any row where zip does not contain any character that is not 0-9 (i.e only 0-9 allowed) where the length is not 5 or 9.
There are few ways you could achieve that.
You can replace [0-9] with _ like
ZIP NOT LIKE '_'
USE LEN() so it's like
LEN(ZIP) NOT IN(5,9)
You are looking for LENGTH()
select * from table WHERE length(ZIP)=5;
select * from table WHERE length(ZIP)=9;
To test for non-numeric values you can use ISNUMERIC():
WHERE ISNUMERIC(ZIP) <> 1
I have a text field which acts a filter field. It checks for equals, contains and starts with. My problem is, with out changing any of my code, can I check for the 'does not contain', 'does not start with' and so on by just using the string i'm passing with something like '!' operator or "<>"?
for example:
I want to get all the records that do not have 'a' in them, so can I pass the string as "!a" or "<>a" or something so that I can get the required records? (I know these two don't work cause I tried.)
You have to use the keyword NOT, e.g.
SELECT * FROM Table WHERE Foo NOT LIKE '%bar%'
Please refer http://www.sqlservercentral.com/Forums/Topic1213442-338-1.aspx
Can solve with case in where clause
I have the following regular expression:
WHERE A.srvc_call_id = '40750564' AND REGEXP_LIKE (A.SRVC_CALL_DN, '[^TEST]')
The row that contains 40750564 has "TEST CALL" in the column SRVC_CALL_DN and REGEXP_LIKE doesn't seem to be filtering it out. Whenever I run the query it returns the row when it shouldn't.
Is my regex pattern wrong? Or does SQL not accept [^whatever]?
The carat anchors the expression to the start of a string. By enclosing the letters T, E, S & T in square brackets you're searching, as barsju suggests for any of these characters, not for the string TEST.
You say that SRVC_CALL_DN contains the string 'TEST CALL', but you don't say where in the string. You also say that you're looking for where this string doesn't match. This implies that you want to use not regexp_like(...
Putting all this together I think you need:
AND NOT REGEXP_LIKE (A.SRVC_CALL_DN, '^TEST[[:space:]]CALL')
This excludes every match from your query where the string starts with 'TEST CALL'. However, if this string may be in any position in the column you need to remove the carat - ^.
This also assumes that the string is always in upper case. If it's in mixed case or lower, then you need to change it again. Something like the following:
AND NOT REGEXP_LIKE (upper(A.SRVC_CALL_DN), '^TEST[[:space:]]CALL')
By upper-casing SRV_CALL_DN you ensure that you're always going to match but ensure that your query may not use an index on this column. I wouldn't worry about this particular point as regular expressions queries can be fairly poor at using indexes anyway and it appears as though SRVC_CALL_ID is indexed.
Also if it may not include 'CALL' you will have to remove this. It is best when using regular expressions to make your match pattern as explicit as possible; so include 'CALL' if you can.
Try with '^TEST' or '^TEST.*'
Your regexp means any string not starting with any of the characters: T,E,S,T.
But your case is so simple, starts with TEST. Why not use a simple like:
LIKE 'TEST%'