I am trying to add emoji like 😋 in my application. In order to make it work, I have to use charset : 'utf8mb4' in database connection. But then my other search query doesn't work and throughs error like this
select id, full_name, profile_pic from users where school_id = 1 and exists (select * from groupmembers where (group_id = '110') and (users.id = groupmembers.user_id)) and full_name like '%d%' COLLATE utf8_bin - ER_COLLATION_CHARSET_MISMATCH: COLLATION 'utf8_bin' is not valid for CHARACTER SET 'utf8mb4
How can I make both works together? I am using adonis.js framework and it uses knex query/
Collations are specific to a character set. If your character set is utf8mb4, then you could use collation utf8mb4_bin but not utf8_bin.
This will become a bit more confusing someday, because MySQL has the intention to change the name of utf8mb4 to utf8. Cf. https://dev.mysql.com/doc/refman/8.0/en/charset-unicode-utf8.html
You can check all the collations allowed by this query:
select collation_name
from information_schema.collation_character_set_applicability
where character_set_name = ##character_set_connection;
I have two databases on MariaDB with InnoDB as engine, with both DB having latin_swedish_ci as collation, but one has latin_swedish_ci as table collation and other utf8_general_ci as table collation, when I execute left excluding join on database with the following query:
SELECT `ct`.`name`
FROM `csv_temp` as `ct`
left join `trans_recs` as `tr` on `ct`.`name` = `tr`.`name`
where `tr`.`name` is null and `ct`.`fk_project_id` = 1
I get correct results on DB and table both with latin_swedish_ci collation but empty set on DB with latin_swedish_ci and table with utf8_general_ci.
Is there an explanation for his behaviour. Thanks in advance.
Does ISNULL on MySql work differently with collation latin_swedish_ci and utf8_general_ci
It does not. ISNULL will work when the cell is null regarding of the collation.
I get correct results on DB and table both with latin_swedish_ci collation but empty set on DB with latin_swedish_ci and table with utf8_general_ci.
Maybe the default is an empty string and not NULL with the collation latin_swedish_ci
select * from table where key='çmyk'
when i run this query on table that have row which's value is 'cmyk'.
the query returns me that row. but values are different. when i search 'çmyk' it returns 'cmyk'.
so what can i do?
MySQL charset: UTF-8 Unicode (utf8)
MySQL connection collation: utf8_unicode_ci
table collation: latin1_swedish_ci
The problem is that the latin1_swedish_ci collation is not only case insensitive, it is umlaut insensitive as well, so the following applies:
Ä = A
Ö = O
etc.
switching to a case sensitive collation in the WHERE clause should work, like so:
select * from table where key='çmyk' collate latin1_general_cs;
with the caveat that this is not good for performance.
mySQL Reference: 9.1.7.8. Examples of the Effect of Collation
Try running the command SET NAMES latin1; and then running your query.
Just got this answer from a previous question and it works a treat!
SELECT username, (SUM(rating)/COUNT(*)) as TheAverage, Count(*) as TheCount
FROM ratings WHERE month='Aug' GROUP BY username HAVING TheCount > 4
ORDER BY TheAverage DESC, TheCount DESC
But when I stick this extra bit in it gives this error:
Documentation #1267 - Illegal mix of
collations
(latin1_swedish_ci,IMPLICIT) and
(latin1_general_ci,IMPLICIT) for
operation '='
SELECT username, (SUM(rating)/COUNT(*)) as TheAverage, Count(*) as TheCount FROM
ratings WHERE month='Aug'
**AND username IN (SELECT username FROM users WHERE gender =1)**
GROUP BY username HAVING TheCount > 4 ORDER BY TheAverage DESC, TheCount DESC
The table is:
id, username, rating, month
Here's how to check which columns are the wrong collation:
SELECT table_schema, table_name, column_name, character_set_name, collation_name
FROM information_schema.columns
WHERE collation_name = 'latin1_general_ci'
ORDER BY table_schema, table_name,ordinal_position;
And here's the query to fix it:
ALTER TABLE tbl_name CONVERT TO CHARACTER SET latin1 COLLATE 'latin1_swedish_ci';
Link
Check the collation type of each table, and make sure that they have the same collation.
After that check also the collation type of each table field that you have use in operation.
I had encountered the same error, and that tricks works on me.
[MySQL]
In these (very rare) cases:
two tables that really need different collation types
values not coming from a table, but from an explicit enumeration, for instance:
SELECT 1 AS numbers UNION ALL SELECT 2 UNION ALL SELECT 3
you can compare the values between the different tables by using CAST or CONVERT:
CAST('my text' AS CHAR CHARACTER SET utf8)
CONVERT('my text' USING utf8)
See CONVERT and CAST documentation on MySQL website.
I was getting this same error on PhpMyadmin and did the solution indicated here which worked for me
ALTER TABLE table CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci
Illegal mix of collations MySQL Error
Also I would recommend going with General instead of swedish since that one is default and not to use the language unless your application is using Swedish.
I think you should convert to utf8
--set utf8 for connection
SET collation_connection = 'utf8_general_ci'
--change CHARACTER SET of DB to utf8
ALTER DATABASE dbName CHARACTER SET utf8 COLLATE utf8_general_ci
--change CHARACTER SET of table to utf8
ALTER TABLE tableName CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci
I also got same error, but in my case main problem was in where condition the parameter that i'm checking was having some unknown hidden character (+%A0)
When A0 convert I got 160 but 160 was out of the range of the character that db knows, that's why database cannot recognize it as character other thing is my table column is varchar
the solution that I did was I checked there is some characters like that and remove those before run the sql command
ex:- preg_replace('/\D/', '', $myParameter);
Check that your users.gender column is an INTEGER.
Try: alter table users convert to character set latin1 collate latin1_swedish_ci;
You need to change each column Collation from latin1_general_ci to latin1_swedish_ci
I got this same error inside a stored procedure, in the where clause. i discovered that the problem ocurred with a local declared variable, previously loaded by the same table/column.
I resolved it casting the data to single char type.
In short, this error is caused by MySQL trying to do an operation on two things which have different collation settings. If you make the settings match, the error will go away. Of course, you need to choose the right setting for your database, depending on what it is going to be used for.
Here's some good advice on choosing between two very common utf8 collations: What's the difference between utf8_general_ci and utf8_unicode_ci
If you are using phpMyAdmin you can do this systematically by working through the tables mentioned in your error message, and checking the collation type for each column. First you should check which is the overall collation setting for your database - phpMyAdmin can tell you this and change it if necessary. But each column in each table can have its own setting. Normally you will want all these to match.
In a small database this is easy enough to do by hand, and in any case if you read the error message in full it will usually point you to the right place. Don't forget to look at the 'structure' settings for columns with subtables in as well. When you find a collation that does not match you can change it using phpMyAdmin directly, no need to use the query window. Then try your operation again. If the error persists, keep looking!
The problem here mainly, just Cast the field like this cast(field as varchar) or cast(fields as date)
I had this problem not because I'm storing in different collations, but because my column type is JSON, which is binary.
Fixed it like this:
select table.field COLLATE utf8mb4_0900_ai_ci AS fieldName
Use ascii_bin where ever possible, it will match up with almost any collation.
A username seldom accepts special characters anyway.
If you want to avoid changing syntax to solve this problem, try this:
Update your MySQL to version 5.5 or greater.
This resolved the problem for me.
I have the same problem with collection warning for a field that is set from 0 to 1. All columns collections was the same. We try to change collections again but nothing fix this issue.
At the end we update the field to NULL and after that we update to 1 and this overcomes the collection problem.
Was getting Illegal mix of collations while creating a category in Bagisto. Running these commands (thank you #Quy Le) solved the issue for me:
--set utf8 for connection
SET collation_connection = 'utf8_general_ci'
--change CHARACTER SET of DB to utf8
ALTER DATABASE dbName CHARACTER SET utf8 COLLATE utf8_general_ci
--change category tables
ALTER TABLE categories CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci
ALTER TABLE category_translations CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci
In my case it was something strange. I read an api key from a file and then I send it to the server where a SQL query is made. The problem was the BOM character that the Windows notepad left, it was causing the error that says:
SQLSTATE[HY000]: General error: 1267 Illegal mix of collations (latin1_swedish_ci,IMPLICIT) and (utf8_general_ci,COERCIBLE) for operation '='
I just removed it and everything worked like a charm
You need to set 'utf8' for all parameters in each Function. It's my case:
SELECT username, AVG(rating) as TheAverage, COUNT(*) as TheCount
FROM ratings
WHERE month='Aug'
AND username COLLATE latin1_general_ci IN
(
SELECT username
FROM users
WHERE gender = 1
)
GROUP BY
username
HAVING
TheCount > 4
ORDER BY
TheAverage DESC, TheCount DESC;
Make sure your version of MySQL supports subqueries (4.1+). Next, you could try rewriting your query to something like this:
SELECT ratings.username, (SUM(rating)/COUNT(*)) as TheAverage, Count(*) as TheCount FROM ratings, users
WHERE ratings.month='Aug' and ratings.username = users.username
AND users.gender = 1
GROUP BY ratings.username
HAVING TheCount > 4 ORDER BY TheAverage DESC, TheCount DESC
I'm looking for a MySQL collation for UTF8 which is case insensitive and distinguishes between "a" and "ä" (or more generally, between umlauted / accented characters and their "pure" form). utf8_general_ci does the former, utf8_bin the latter, bot none does both. If there is no such collation, what can I do to get as close as possible in a WHERE clause?
My recommendation would be to use utf8_bin and in your WHERE clause, force both sides of your comparison to upper or lower case.
It works fine here with utf8_german2_ci as collation:
SELECT * FROM tablename WHERE fieldname LIKE "würz%" COLLATE utf8_german2_ci
I checked utf8_bin like this
CREATE TABLE tmp2 (utf8_bin VARCHAR(20) CHARACTER SET utf8 COLLATE utf8_bin);
INSERT INTO tmp2 VALUES ('nói');
select * from tmp2 where utf8_bin='noi';
You could try utf8_swedish_ci, it's both case insensitive and distinguishes between a and ä (but treats e.g. ü like y).
Collations are language-dependent, and it seems German doesn't have its own collation in MySQL. (I had a look at your profile, which says you're German.)