How can I use SQL/PostgreSQL to do something like this (psuedo code):
UPDATE table
SET content = replace(content, 'padding-top: $VAR', 'padding-top: 30px')
WHERE user = 1;
The $VAR is an unknown value, like 80%, 50% or 80px. How could I do this?
You could use regexp_replace:
UPDATE table
SET content = regexp_replace(content, '^padding-top: .*$', 'padding-top: 30px')
WHERE user = 1;
Note that as its name suggests, regexp_replace takes a regular expression. So I am using ^, $ for the beginning and the end, and .* which means "match with any sequence of characters" (. means "match with any character" and * means "match the previous symbol as many times as possible").
Related
I need some help with the next. I have a field text in SQL, this record a list of times sepparates with '|'. For example
'14613|15474|3832|148|5236|5348|1055|524' Each value is a time in milliseconds. This field could any length, for example is perfect correct '3215|2654' or '4565' (only 1 value). I need get this field and replace all number with -1000 value.
So '14613|15474|3832|148|5236|5348|1055|524' will be '-1000|-1000|-1000|-1000|-1000|-1000|-1000|-1000'
Or '3215|2654' => '-1000|-1000' Or '4565' => '-1000'.
I try use regexp_replace(times_field,'[[:digit:]]','-1000','g') but it replace each digit, not the complete number, so in this example:
'3215|2654' than must be '-1000|-1000', i get:
'-1000-1000-1000-1000|-1000-1000-1000-1000', I try with other combinations and more options of regexp but i'm done.
Please need your help, thanks!!!.
We can try using REGEXP_REPLACE here:
UPDATE yourTable
SET times_field = REGEXP_REPLACE(times_field, '\y[0-9]+\y', '-1000', 'g');
If instead you don't really want to alter your data but rather just view your data this way, then use a select:
SELECT
times_field,
REGEXP_REPLACE(times_field, '\y[0-9]+\y', '-1000', 'g') AS times_field_replace
FROM yourTable;
Note that in either case we pass g as the fourtb parameter to REGEXP_REPLACE to do a global replacement of all pipe separated numbers.
[[:digit:]] - matches a digit [0-9]
+ Quantifier - matches between one and unlimited times, as many times as possible
your regexp must look like
regexp_replace(times_field,'[[:digit:]]+','-1000','g')
How can I find matching line in char/string type column?
For example let say I have column called text and some row has content of:
12345\nabcdf\nXKJKJ
(where \n are real new lines)
Now I want to find related row if any of lines match. For example, I have value 12345,
then it should find match. But if I have value 123, It would not.
I tried using like but it finds in both cases, when I have matching value (like 12345) and partially matching value (like 123).
For example something like this, but to have boundary for checking whole line:
SELECT id
FROM my_table
WHERE text like [SOME_VALUE]
Update
Maybe its not yet clear what Im asking. But basically I want something equivalent what you can do with regular expression,
like this: https://regexr.com/5akj1
Here regular expression /^123$/m would not match my string, it would only match if it would have been with pattern /^12345$/m (when I use pattern, value is dynamic, so pattern would change depending what value I got).
You may use regexp_replace and then check that the replaced string is not equal to the original column value:
select count(*)
from dummy
where regexp_replace(mytext, '(?m)^1234$', '') <> mytext;
You have a demo here.
Bear in mind that I have used the (?m) modifier, which makes ^ and $ match begin and end of line instead of begin and end of string.
You should be able to use ~ for matching:
where mytext ~ '(\n|^)1234(\n|$)'
I am using Snowflake SQL. I would like to remove characters from a string after a special character ~. How can I do that?
here is the whole scenario. Let me explain. I do have a string like 'CK#123456~fndkjfgdjkg'. Now, i want only the number after #.And not anything after ~. This is number length varies for that field value. It might be 1 or 5 or 3. And i want to add the condition in where class where this number is equal to check_num from other table after joining. I am trying REGEXP_SUBSTR(A.SRC_TXT, '(?<=CK#)(.+?\b)') = C.CHK_NUM in the where condition. I am getting the error as 'No repititive argument after ?'
You can use a regex for this
-- To remove just the character after a ~
select regexp_replace('fo~o bar','~.', '');
-- returns 'fo bar'
--If you want to keep the ~
select regexp_replace('fo~o bar','~.', '~');
-- returns 'fo~ bar'
--If you want to remove everything after the ~
select regexp_replace('fo~o bar','~.*', '');
--returns 'fo'
If you need to remove other specific character sets after a ~, you can probably do this with a slightly more complicated regex, but I'd need examples of your desired input/output to help with that.
EDIT for updated question
This regex replace should get what you need.
select regexp_replace('CK#123456~fndkjfgdjkg','CK#(\\d*)~.*', '\\1');
-- returns 123456
(\\d*) gets ANY number of digits in a row, and the \\1 causes it to replace the match with what was in the first set of parenthesis, which is your list of digits. the CK# and ~.* are there to make sure the whole string gets matched and replaced.
If the CK# can vary as well, you can use .*? like this.
select regexp_replace('ABCD123HI#123456~fndkjfgdjkg','.*?#(\\d*)~.*', '\\1')
-- returns 123456
I'd probably do something like the following, easy enough but not as cool as RegEx type of functions.
set my_string='fooo~12345';
set search_for_me = '~';
SELECT SUBSTR($my_string, 1, DECODE(position($search_for_me, $my_string), 0, length($my_string), position($search_for_me, $my_string)));
I hope this helps...Rich
It looks like lookahead and lookbehinds are not supported in REGEXP functions, they seem to work in the PATTERN clause of a LIST command. Snowflake documentation makes no mention either way of lookahead or lookbehinds.
In your example:
It seems that the query engine is looking for that repeating argument, where you are attempting a lookbehind
You have not specified what you wanted extracted. You have two capture groups, but in this scenario everything would be returned
Since you are looking to remove everything after ~ you have a delimiter, why not use it in your REGEXP_SUBSTR function?
Try the following:
SELECT $1,REGEXP_SUBSTR($1,'\\w+#(.+?)~',1,1,'is',1)
FROM VALUES
('CK#123456~fndkjfgdjkg')
,('QH#128fklj924~fndkjfgdjkg')
;
This looks for:
One or more word characters
Followed by #
Capturing one or more characters upto and not including ~
Returns the characters within the capture group
You can change the .+? to \\d+? to make sure the pattern is only digits. Backslashes must be escaped with a backslash.
The descriptions for each argument of the function can be found here:
https://docs.snowflake.net/manuals/sql-reference/functions/regexp_substr.html
You could check this!!
select substr('CK#123456~fndkjfgdjkg',4,6) from dual;
OUTPUT
123456
https://docs.snowflake.net/manuals/sql-reference/functions/substr.html
I need to return the fields that have more than one . in a specific column.
Now I have this query:
select *
from table
where column ~ '\.{2,}?';
But for some reason it returns nothing. If I use something like 'A{2,}?' it works. Apparently the problem is the dot.
It returns null since the dots are not next two each other. You have to consider the occurrences of the characters in the order of your regex meta characters. You could try this instead:
select *
from table
where column ~ '\.\d{3}\.';
Or instead of just focusing on the dot characters start parsing the string as a whole and consider the numbers as well:
where column ~ '^\d{3}\.\d{3}\.';
Why not just use like?
where column like '%.%.%'
what is difference between these two sql statements
1- select * from tblperson where name not like '[^AKG]%';
2- select * from tblperson where name like '[AKG]%';
showing same results: letter starting from a,k,g
like '[^AKG]% -- This gets you rows where the first character of name is not A,K or G. ^ matches any single character not in the specified set or a specified range of characters. There is one more negation not. So when you say name not like '[^AKG]%' you get rows where the first character of name is A,K or G.
name like '[AKG]% -- you get rows where the first character of name is A,K or G.
The wildcard character [] matches any character in a specified range or a set of characters. In your case it is a set of characters.
So both the conditions are equivalent.
You are using a double 'NOT'. The carrot '^' in your first character match is shorthand for 'not', so you are evaluating 'not like [not' AKG]% IE not like '[^AKG]%'.
1)In the first query you are using 'Not' and '^' basically it is Not twice so it cancels outs
therefore your query is 'Not Like [^AKG]' ==> 'Like [AKG]'
^ a.k.a caret or up arrow.
The purpose of this symbol is to provide a match for any characters not listed within the brackets [] , meaning that normally it wouldn't provide a result for anything that starts with AKG, but since you added the word NOT to the query , you are basically cancelling the operator, just as if you were doing in math :
(- 1) * (- 1)