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I know that I can combine multiple columns in mysql by doing:
SELECT CONCAT(zipcode, ' - ', city, ', ', state) FROM Table;
However, if one of the fields is NULL then the entire value will be NULL. So to prevent this from happening I am doing:
SELECT CONCAT(zipcode, ' - ', COALESE(city,''), ', ', COALESCE(state,'')) FROM Table;
However, there still can be situation where the result will look something like this:
zipcode-, ,
Is there a way in MySQL to only have to comma and the hyphen if the next columns are not NULL?
There is actually a native function that will do this called Concat with Separator (concat_ws)!
Specifically, it seems that what you would need is:
SELECT CONCAT_WS(' - ',zipcode, NULLIF(CONCAT_WS(', ',city,state),'')) FROM TABLE;
This should account for all of the null cases you allude to.
However, it is important to note that a blank string ('') is different than a NULL. If you want to address this in the state/city logic you would add a second NULLIF check inside the second CONCAT_ws for the case where a city or a state would be blank strings. This will depend on the database's regard for the blank field and whether you are entering true NULLS into your database or checking the integrity of the blank data before you use it. Something like the following might be slightly more robust:
SELECT CONCAT_WS(' - ', zipcode, NULLIF(CONCAT_WS(', ', NULLIF(city, ''), NULLIF(state, '')), '')) FROM TABLE;
For more, check out the native documentation on concat_ws() here:
https://dev.mysql.com/doc/refman/8.0/en/string-functions.html#function_concat-ws
I think you need something like this
Set #zipcode := '12345';
Set #city := NULL;
Set #state := NULL;
SELECT CONCAT(#zipcode, ' - ', COALESCE(#city,''), ', ', COALESCE(#state,''));
Result: 12345 - ,
SELECT CONCAT(#zipcode, IF(#city is NULL,'', CONCAT(' - ', #city)), IF(#state is NULL,'', CONCAT(', ',#state)))
Result 12345
You need to make the output of the separators conditional on the following values being non-NULL. For example:
SELECT CONCAT(zipcode,
CASE WHEN city IS NOT NULL OR state IS NOT NULL THEN ' - '
ELSE ''
END,
COALESCE(city, ''),
CASE WHEN city IS NOT NULL AND state IS NOT NULL THEN ', '
ELSE ''
END,
COALESCE(state, '')
) AS address
FROM `Table``
Output (for my demo)
address
12345 - San Francisco, CA
67890 - Los Angeles
34567 - AL
87654
Demo on dbfiddle
I have a table of UK postcodes. All of them are in different format, some are capitalized with white space some are not. What I want to do is format them so they can follow the UK postcode standard. For instance AB1 2BB.
I used this query for the purpose which does work, but some postcodes have a longer or shorter first part so it does not succeed for all.
SELECT UPPER(INSERT((REPLACE(postcode , ' ', '')) , 4, 0, ' ')) AS postcode
However if I try to do it the other way around
SELECT UPPER(INSERT((REPLACE(postcode , ' ', '')) , -4, 0, ' ')) AS postcode
It does not work and returns all the postcodes glued together e.g AB12BB
What I want is to put a space before the last 3 characters.
I think you want:
select concat_ws(' ',
left(replace(postcode, ' ', ''), 3),
right(replace(postcode, ' ', ''), 3
) as standardized_postcode
Insert a space at the 3th char from the end of the string, after you remove all the spaces:
SELECT UPPER(INSERT(REPLACE(postcode , ' ', ''), LENGTH(REPLACE(postcode , ' ', '')) - 2, 0, ' ')) AS postcode
It sounds like you're going to be dealing with postcodes like this:
LS10 1DH
LS101DH
LS63DR
etc. We should start by removing all of the spaces:
REPLACE(postcode,' ','') -- LS10 1DH becomes LS101DH
taking the last 3 characters:
RIGHT(REPLACE(postcode,' ',''), 3) -- 1DH
and all of the characters up to the 3rd from last:
LEFT(REPLACE(postcode,' ',''), LEN(REPLACE(postcode,' ','')) - 3))
Then use CONCAT to bring it all together:
SET #postcode = 'LS101DH';
SELECT CONCAT(LEFT(REPLACE(#postcode,' ',''), LENGTH(REPLACE(#postcode,' ','')) - 3),
' ', -- add a space in
RIGHT(REPLACE(#postcode,' ',''), 3));
for pc in postcodes:
print('{} {}'.format(pc[:-3], pc[-3:]))
Seems to work for a given list of UK postcodes for me.
Please take a look at a table below:
I need "the last part" of "what I have" to be number if it's all number and string if it contains character.
In Excel I've achieved this with the following function (as shown above):
=IFERROR(VALUE(TEXT(D2;"0"));TEXT(D2;"0"))
However I want to do this in mySQL in order to compute more effectively.
I've "floated" somwhere around CASE with CAST or CONVERT and also TRIM functions, but I haven't been able to put up something sensical.
A nice "bonus" would be to extract "the part part" by looking for the last "" character (so first "" from right of the string) but no idea at all how to achieve that.
Use SUBSTRING_INDEX.
Query
SELECT
CASE
WHEN SUBSTRING_INDEX(records.data, '_', -1) > 1 # is int check '00004949' returns 1
THEN SUBSTRING_INDEX(records.data, '_', -1) + 0 # converts '00004949' to 4949
ELSE SUBSTRING_INDEX(records.data, '_', -1)
END
AS word
FROM (
SELECT "TRA_PL_NWL_EMA_NWLY_DAI_000_20170610_IN1_01P002bc" AS DATA
UNION
SELECT "TRA_PL_NWL_EMA_NWLY_DAI_000_2017_0909_JET_00004949" AS DATA
) records
Result
word
----------
01P002bc
4949
Following query will somewhat achieve the task:
SELECT
case
when SUBSTRING_INDEX(value, "_", -1) REGEXP('(^[0-9]+$)')
then Trim(Leading 0 from SUBSTRING_INDEX(value, "_", -1))
else SUBSTRING_INDEX(value, "_", -1)
end as Value
From yourtable;
Click here for Demo
Hope it helps!
I hope this is what u want.
At least it does what you have asked for.
SELECT
CASE
WHEN (
CONVERT(
substring(
txt,
LENGTH(txt) - LOCATE('_', REVERSE(txt))+2,
length(txt)
)
, signed integer
)
) = 0
THEN substring(
txt,
LENGTH(txt) - LOCATE('_', REVERSE(txt))+2,
length(txt)
)
ELSE CONVERT(
substring(
txt,
LENGTH(txt) - LOCATE('_', REVERSE(txt))+2,
length(txt)
)
, signed integer
)
END as NUMBER
from test.test
This is my test Table and result of SQL:
txt NUMBER
DA_DA_ADAD_ADAD_ADAD_asd123 asd123
DA_DA_ADAD_ADAD_ADAD_000123 123
DA_DA_ADAD_ADAD_ADAD_444 444
DA_DA_ADAD_ADAD_ADAD_bsd123 bsd123
DA_DA_ADAD_ADAD_ADAD_csd123 csd123
DA_DA_ADAD_ADAD_ADAD_dsd123 dsd123
Currently I'm working on a database redesign project. A large bulk of this project is pulling data from the old database and importing it into the new one.
One of the columns in a table from the old database is called 'name'. It contains a forename and a surname all in one field (ugh). The new table has two columns; forenames and surname. I need to come up with a clean, efficient way to split this single column into two.
For now I'd like to do everything in the same table and then I can easily transfer it across.
3 columns:
Name (the forename and surname)
Forename (currently empty, first half of name should go here)
Surname (currently empty, second half of name should go here)
What I need to do: Split name in half and place into forename and surname
If anyone could shed some light on how to do this kind of thing I would really appreciate it as I haven't done anything like this in SQL before.
Database engine: MySQL
Storage engine: InnoDB
A quick solution is to use SUBSTRING_INDEX to get everything at the left of the first space, and everything past the first space:
UPDATE tablename
SET
Forename = SUBSTRING_INDEX(Name, ' ', 1),
Surname = SUBSTRING_INDEX(Name, ' ', -1)
Please see fiddle here. It is not perfect, as a name could have multiple spaces, but it can be a good query to start with and it works for most names.
Try this:
insert into new_table (forename, lastName, ...)
select
substring_index(name, ' ', 1),
substring(name from instr(name, ' ') + 1),
...
from old_table
This assumes the first word is the forename, and the rest the is lastname, which correctly handles multi-word last names like "John De Lacey"
For the people who wants to handle fullname: John -> firstname: John, lastname: null
SELECT
if( INSTR(`name`, ' ')=0,
TRIM(SUBSTRING(`name`, INSTR(`name`, ' ')+1)),
TRIM(SUBSTRING(`name`, 1, INSTR(`name`, ' ')-1)) ) first_name,
if( INSTR(`name`, ' ')=0,
null,
TRIM(SUBSTRING(`name`, INSTR(`name`, ' ')+1)) ) last_name
It works fine with John Doe. However if user just fill in John with no last name, SUBSTRING(name, INSTR(name, ' ')+1)) as lastname will return John instead of null and firstname will be null with SUBSTRING(name, 1, INSTR(name, ' ')-1).
In my case I added if condition check to correctly determine lastname and trim to prevent multiple spaces between them.
This improves upon the answer given, consider entry like this "Jack Smith Smithson", if you need just first and last name, and you want first name to be "Jack Smith" and last name "Smithson", then you need query like this:
-- MySQL
SELECT
SUBSTR(full_name, 1, length(full_name) - length(SUBSTRING_INDEX(full_name, ' ', -1)) - 1) as first_name,
SUBSTRING_INDEX(full_name, ' ', -1) as last_name
FROM yourtable
Just wanted to share my solution. It also works with middle names. The middle name will be added to the first name.
SELECT
TRIM(SUBSTRING(name,1, LENGTH(name)- LENGTH(SUBSTRING_INDEX(name, ' ', -1)))) AS firstname,
SUBSTRING_INDEX(name, ' ', -1) AS lastname
I had a similar problem but with Names containing multiple names, eg. "FirstName MiddleNames LastName" and it should be "MiddleNames" and not "MiddleName".
So I used a combo of substring() and reverse() to solve my problem:
select
SystemUser.Email,
SystemUser.Name,
Substring(SystemUser.Name, 1, instr(SystemUser.Name, ' ')) as 'First Name',
reverse(Substring(reverse(SystemUser.Name), 1, instr(reverse(SystemUser.Name), ' '))) as 'Last Name',
I do not need the "MiddleNames" part and maybe this is not the most efficient way to solve it, but it works for me.
Got here from google, and came up with a slightly different solution that does handle names with more than two parts (up to 5 name parts, as would be created by space character). This sets the last_name column to everything to the right of the 'first name' (first space), it also sets full_name to the first name part. Perhaps backup your DB before running this :-) but here it is it worked for me:
UPDATE users SET
name_last =
CASE
WHEN LENGTH(SUBSTRING_INDEX(full_name, ' ', 1)) = LENGTH(full_name) THEN ''
WHEN LENGTH(SUBSTRING_INDEX(full_name, ' ', 2)) = LENGTH(full_name) THEN SUBSTRING_INDEX(del_name, ' ', -1)
WHEN LENGTH(SUBSTRING_INDEX(full_name, ' ', 3)) = LENGTH(full_name) THEN SUBSTRING_INDEX(del_name, ' ', -2)
WHEN LENGTH(SUBSTRING_INDEX(full_name, ' ', 4)) = LENGTH(full_name) THEN SUBSTRING_INDEX(del_name, ' ', -3)
WHEN LENGTH(SUBSTRING_INDEX(full_name, ' ', 5)) = LENGTH(full_name) THEN SUBSTRING_INDEX(del_name, ' ', -4)
WHEN LENGTH(SUBSTRING_INDEX(full_name, ' ', 6)) = LENGTH(full_name) THEN SUBSTRING_INDEX(del_name, ' ', -5)
ELSE ''
END,
full_name = SUBSTRING_INDEX(full_name, ' ', 1)
WHERE LENGTH(name_last) = 0 or LENGTH(name_last) is null or name_last = ''
SUBSTRING_INDEX didn't work for me in SQL 2018, so I used this:
declare #fullName varchar(50) = 'First Last1 Last2'
declare #first varchar(50)
declare #last varchar(50)
select #last = right(#fullName, len(#fullName)-charindex(' ',#fullName, 1)), #first = left(#fullName, (charindex(' ', #fullName, 1))-1);
Yields #first = 'First', #last = 'Last1 Last2'
In the below piece of code, I am creating an Address field by concatenating various parts of an address.
However, if for instance address2 was empty, the trailing , will still be concatenated into Address.
This means if all fields were empty, I end up with a result of ,,,,.
If address1 is "House Number" and everything else is empty, I end up with House Number,,,,.
CONCAT( COALESCE(address1,'') , ', ' ,
COALESCE(address2,'') , ', ' ,
COALESCE(address3,'') , ', ' ,
COALESCE(city,'') , ', ' ,
COALESCE(zip, '')
) AS Address,
Is there some way of conditionally placing the commas between address parts only if the content of an address part is not empty.
Such as something along the lines of (pseudo-code) IF(address1) is NULL use '' ELSE use ','
Thank you.
CONCAT_WS(', ',
IF(LENGTH(`address1`),`address1`,NULL),
IF(LENGTH(`address2`),`address2`,NULL),
IF(LENGTH(`address3`),`address3`,NULL),
IF(LENGTH(`city`),`city`,NULL),
IF(LENGTH(`zip`),`zip`,NULL)
)
Using CONCAT_WS as Mat says is a very good idea, but I thought I'd do it a different way, with messy IF() statements:
CONCAT( COALESCE(address1,''), IF(LENGTH(address1), ', ', ''),
COALESCE(address2,''), IF(LENGTH(address2), ', ', ''),
COALESCE(address3,''), IF(LENGTH(address3), ', ', ''),
COALESCE(city,''), IF(LENGTH(city), ', ', ''),
COALESCE(zip,''), IF(LENGTH(address1), ', ', ''),
) AS Address,
The IF()s check if the field has a length and if so returns a comma. Otherwise, it returns an empty string.
try with MAKE_SET
SELECT MAKE_SET(11111,`address1`,`address2`,`address3`,`city`,`zip`) AS Address
It will returns a string with all NOT NULL value separated by ,
CONCAT_WS(', ',
NULLIF(`address1`,''),
NULLIF(`address2`,''),
NULLIF(`address3`,''),
NULLIF(`city`,''),
NULLIF(`zip`,'')
)
CONCAT_WS combines non-NULL strings.
NULLIF writes NULL if left and right side are equals. In this case if values are equals an empty sting ''.