I have a dataset where the values are different, and I want to bring them into a single format.The values are stored as varchar
For ex.
1st Case: 1.23.45 should be 123.45
2nd Case: 125.45 should be 125.45
The first one, has two decimals. I want to remove the first decimal only(if there are 2) else let the value be as it is.
How do I do this?
I tried using replace(Qty,'.',''). But this is removing of them.
I think this can do (although I am not 100% sure about corner cases)
SET Qty = SUBSTRING(Qty, 1, LOCATE(Qty, '.') - 1) + SUBSTRING(Qty, LOCATE(Qty, '.') + 1, LENGTH(Qty) - LOCATE(Qty, '.') - 1)
WHERE LENGTH(Qty) - LENGTH(REPLACE(Qty, '.', '')
You can use a regular expression to handle this case.
Assuming there are only two decimals in your string the below query should be able to handle the case.
select (value,'^(\d+)(\.)?(\d+\.\d+)$',concat('$1','$2')) as a
Here we are matching a regular expression pattern and capturing the following
digits before first decimal occurrence in group one
digits before and after last decimal occurrence including the last decimal in group two.
Following that we are concatenating the two captured groups.
Note that the first decimal has been made optional using ? character and hence we are able to handle both type of cases.
Even if there are more than two decimal cases, I believe a properly constructed regular expression should be able to handle it.
Related
I have a MySQL table setup where one column's values are a string of comma-separated True/False values (1s or 0s). For example, in the column, one field's value may be "0,1,0,0,0,0,1,1,0" and another may be "1,0,0,1,1,1,0,0,0" (note: these are NOT 9 separate columns, but a string in one column). I need to QUERY the MySQL table for elements that are "true"(1) for the "nth element" of that column's value/string.
So, if I was looking for rows, with a specific column, where the 3rd element of the column's value was 1, it would produce a list of results. So, in this case, I would only be searching for "1" in the fth place (12345 = X,X,X...) of the string (X,X,1,X,X,X,X,X,X,X). How can I query this?
This is a crude example of what I am trying to do ...
"SELECT tfcolumn FROM mytable WHERE substr({tfcolumn}, 0, 5)=1"
{tfcolumn} represents the column value
5 represents the 5th position of the string
=1 represents what I need that position to equal to.
Please help. Thanks
You can't. Once you put a serialized data type into a column in SQL (like comma separated lists, or JSON objects) you are preventing yourself from performing any query on the data in those columns. You have to pull the data in a different way and then use a program like python, VB, etc to get the comma separated values you are looking for.
Unless you want to deal with trying to make this mess of a query work...
I would recommend changing your table structure before it's too late. Although it is possible, it is not optimized in a format that a DBMS recognizes. Because of that the DBMS will spend a significant amount of time going through every record to parse the csv values which is something that it was not meant to be doing. Doing the query in SQL will take as much time (if not more time) than just pulling all the records and searching with a tool that can do it properly.
If the column contains values exactly like the ones you posted, then the Nth element is at the 2 * N - 1 position in the comma separated list.
So do this:
SELECT tfcolumn
FROM tablename
WHERE substr(tfcolumn, 2 * 5 - 1, 1) = '1'
Replace 5 with the index that you search for.
See the demo.
Or remove all commas and get the Nth char:
SELECT tfcolumn
FROM tablename
WHERE substr(replace(tfcolumn, ',', ''), 5, 1) = '1'
See the demo.
Try this
if substring_index(substring_index('0,1,0,0,0,0,1,1,0',',',3),',',-1)='1'
The first argument can be your column name. The second argument (',') tells the function that the string is comma-separated. The third argument takes the first 3 elements of the string. So, the output of inner substring_index is '0,1,0'.
The outer substring_index has -1 as the last argment. So, it starts counting in reverse direction & takes only 1 element starting from right.
For example, if the value in a particular row is '2,682,7003,14,185', then the value of substring_index(substring_index('2,682,7003,14,185',',',3),',',-1) is '7003'.
So I have a column of strings in a format like this: '123.123.123.123.123'.
I need to cut the string to the first two numbers like so: '123.123' that way I can GROUP BY the cut string to get the results needed.
I can do this easily by using SUBSTRING_INDEX(Version, '.', 2) however the problem arises when the second number part has multiple 0's therefore giving me duplicate entries in the query.
e.g. (10.00, 10.0) and 10.404, 10.4040 etc.
Is there a way to trim all unwanted zeros off the end of the string?
Note: I can only use straight MySQL or functions in this case.
EDIT:
I can get the desired result by replacing the first instance of '.0', trim the extra zeros and then replace the '.0' back
REPLACE(TRIM(TRAILING '0' FROM REPLACE(SUBSTRING_INDEX(Version, '.', 2), '.0', '^a')), '^a', '.0')
This probably is not the best option performance wise - therefore I will wait for others before accepting my own.
If you are only working with the first two components, then convert the values to a number, say:
cast(substring_index(version, '.', 2) + 0 as decimal(10, 4))
This will give everything with equal numeric values the same representation.
EDIT:
If you want to remove the trailing zeros from the end of the string, you can use this trick:
replace(rtrim(replace(substring_index(version, '.', 2), '0', ' ')), ' ', '0')
This replaces the zeros with spaces, then uses rtrim() and converts them back to zeroes.
I have a table with about 50,000 records. One of the fields is a "imploaded" field consisting of variable number of parameters from 1 to 800. I need to replace all parameters to 0.
Example:
1 parameter 3.45 should become 0.00
2 parameters 2.27^11.03 should become 0.00^0.00
3 parameters 809.11^0.12^3334.25 should become 0.00^0.00^0.00
and so on.
Really I need to replace anything between ^ with 0.00 ( for 1 parameter it should be just 0.00 without ^).
Or I need somehow count number of ^, generate string like 0.00^0.00^0.00 ... and replace it. The only tool available is MySqlWorkbench.
I would appreciate any help.
There is no regex replace capability built in to MySQL.
You can, however, accomplish your purpose by doing what you suggested -- counting the number of ^ and crafting a string of replacement values, with this:
TRIM(TRAILING '^' FROM REPEAT('0.00^',(LENGTH(column) - LENGTH(REPLACE(column,'^','')) + 1)));
From inside to outside, we calculate the number of values by counting the number of delimiters, and adding 1 to that count. We count the delimiters by comparing the length of the original string, against the length of the same string with the delimiters stripped out using REPLACE(...,'^','') to replace every ^ with nothing.
The REPEAT() function builds a string by repeating a string expression n number of times.
This results in a spurious ^ at the end of the string, which we remove easily enough with TRIM(TRAILING '^' FROM ...).
SELECT t1.*, ... the expression above ... FROM table_name t1, from your table to verify the results of this logic (replacing column with the actual name of the column), then you can UPDATE table SET column = ... to modify the values. once you are confident in the logic.
Note, of course, that this is indicative of a problematic database design. Each column should contain a single atomic value, not a "list" of values, as this question seems to suggest.
I'm working on a query in which I have a column of account numbers, which I've formatted by using a CONCAT statement to make the numbers 1-11111 instead of 11111.
There is a column with prior account numbers, however this value is NULL unless there is actually a prior account number. To try to only format the account numbers if they exist, I did this:
IFNULL(CONCAT(LEFT(a.prior_acct, 1), '-', RIGHT(a.prior_acct, 5)), 0) AS prior_account
Now, this is properly formatting the account numbers that are there, into the 1-11111 format. However the NULL fields are returning with the hypen and not a 0 (equally acceptable would be a blank space).
I tried adding in an extra set of parenthesis around the full concat statement to see if that would take away the hyphen but no luck!
What am I missing? TIA!
Your query should work as it is unless you are actually storing empty string in prior_acct , not NULL.
SELECT IFNULL(CONCAT(LEFT('', 1),'-',RIGHT('', 5)),0); -- outputs -
SELECT IFNULL(CONCAT(LEFT(null, 1),'-',RIGHT(null, 5)),0); --outputs 0
It's not Oracle where empty string and NULL are the same. If you need to treat empty string as null , you need to specify it's explicitly. One way is
IFNULL(CONCAT(
IF(
TRIM(LEFT('', 1))='',NULL, TRIM(LEFT('', 1))
),
'-', RIGHT(a.prior_acct, 5)), 0) AS prior_account
Consider the string "55,33,255,66,55"
I am finding ways to count number of occurence of a specific characters ("55" in this case) in this string using mysql select query.
Currently i am using the below logic to count
select CAST((LENGTH("55,33,255,66,55") - LENGTH(REPLACE("55,33,255,66,55", "55", ""))) / LENGTH("55") AS UNSIGNED)
But the issue with this one is, it counts all occurence of 55 and the result is = 3,
but the desired output is = 2.
Is there any way i can make this work correct? please suggest.
NOTE : "55" is the input we are giving and consider the value "55,33,255,66,55" is from a database field.
Regards,
Balan
You want to match on ',55,', but there's the first and last position to worry about. You can use the trick of adding commas to the frot and back of the input to get around that:
select LENGTH('55,33,255,66,55') + 2 -
LENGTH(REPLACE(CONCAT(',', '55,33,255,66,55', ','), ',55,', 'xxx'))
Returns 2
I've used CONCAT to pre- and post-pend the commas (rather than adding a literal into the text) because I assume you'll be using this on a column not a literal.
Note also these improvements:
Removal of the cast - it is already numeric
By replacing with a string one less in length (ie ',55,' length 4 to 'xxx' length 3), the result doesn't need to be divided - it's already the correct result
2 is added to the length because of the two commas added front and back (no need to use CONCAT to calculate the pre-replace length)
Try this:
select CAST((LENGTH("55,33,255,66,55") + 2 - LENGTH(REPLACE(concat(",","55,33,255,66,55",","), ",55,", ",,"))) / LENGTH("55") AS UNSIGNED)
I would do an sub select in this sub select I would replace every 255 with some other unique signs and them count the new signs and the standing 55's.
If(row = '255') then '1337'
for example.