MySQL SELECT WHERE 'a' IN (`field`) - mysql

I know it is not an appropriate technique to have a structure of MySQL table as such, but I have to work with such. The problem is, that the field in table has value with comma seperated integers, like "1,3,5,7,10" and I want the query to return rows, in which field has a to the query passed number in it, like:
SELECT * FROM `table` WHERE '5' IN (`field_in_table`)
However, it does not work, if, in this case, '5' is not the first number in the field.
Any advises, how to solve that?
Thanks in advance,
Regards,
Jonas

Have a look at
FIND_IN_SET
Returns a value in the range of 1 to N
if the string str is in the string
list strlist consisting of N
substrings. A string list is a string
composed of substrings separated by
“,” characters. If the first argument
is a constant string and the second is
a column of type SET, the
FIND_IN_SET() function is optimized to
use bit arithmetic. Returns 0 if str
is not in strlist or if strlist is the
empty string.

You could use WHERE field_in_table LIKE '%5%' instead.
Of course, the problem would be, '1,59,98' would return as wel.

SELECT * FROM table WHERE field_in_table LIKE '%5'");
should work

You could try
SELECT *
FROM table
WHERE '%,5,%' LIKE field_in_table OR
'%,5' LIKE field_in_table OR
'5,%' LIKE field_in_table;
A better approach might be to use regular expressions, a subject on which I am not an authority.

SELECT *
FROM table
WHERE FIELD LIKE '%,5,%' OR
FIELD LIKE '5,%' OR
FIELD LIKE '%,5'

Related

find string in first 10 characters

I have a table with fields containing html code. I would like to select only those rows where htmlfield contain string "<p>[[{"fid":" but only in first 10 characters of the html field (this field contains more of such strings and I want to find only fields that contain the string in the beginning).
Is it possible to do such select?
You can use a SUBSTRING() to grab the fields with that string in them.
SELECT field1
FROM TableName
WHERE SUBSTRING(field1, 1, 12) = '<p>[[{"fid":'
Example
You can also try using the LIKE function. Where you can use the % wildcard at the end of your string to get fields that start with that string.
SELECT field1
FROM TableName
WHERE field1 LIKE '<p>[[{"fid":%'
Example
Do it like this:
select SUBSTRING(field_name,1, 10) from table_name;
It will display 10 characters only for that specific field.
Hope it helps

Mysql SELECT all rows where char exists in value but not the last one

I need a SELECT query in MYSQL that will retrieve all rows in one table witch field values contain "?" char with one condition: the char is not the last character
Example:
ID Field
1 123??see
2 12?
3 45??78??
Returning rows would then be those from ID 1 and 3 that match the condition given
The only statement I have is:
SELECT *
FROM table
WHERE Field LIKE '%?%'
But, the MySQL query does not solve my problem..
The LIKE expressions also support a wildcard "_" which matches exactly one character.
So you can write an expression like the example below, and know that your "?" will not be the last character in the string. There must be at least one more character.
WHERE intrebare LIKE '%?_%'
Re comment from #JohnRuddell,
Yes, that's true, this will match the string "??" because a "?" exists in a position that is not the last character.
It depends whether the OP means for that to be a match or not. The OP says the string "45??78??" is a match, but it's not clear if they would intend that "4578??" to be a match.
An alternative is to use a regular expression, but this is a little more tricky because you have to escape a literal "?", so it won't be interpreted as a regexp metacharacter. Then also escape the escape character.
WHERE intrebare REGEXP '\\?[^?]'
you can just add an additional where where the last character is not a ?
SELECT *
FROM intrebari
WHERE intrebare LIKE '%?%' AND intrebare NOT LIKE '%?'
you could also do it like this
SELECT *
FROM intrebari
WHERE intrebare LIKE '%?%' AND RIGHT(intrebare,1) <> '?'
DEMO

How do I get the type of a variable in MySQL?

I'm trying to change a table field that contains decimal numbers from varchar(255) to decimal(12,2). And before I do that, I'd like to find out if there is information that would get deleted in the process: are there any rows where this field contains something other than a decimal(12,2).
I'm stumped how to do this. Apparently there isn't a string function like is_numeric() in PHP. I already tried casting the field to decimal and then comparing it with the original string, but this returns TRUE even for obvious cases where it should not:
select ('abc' = convert('abc', decimal(12,2)));
returns 1
Any help? How do I find out if a string contains something other than a decimal in MySQL? Thanks.
Stupid me, I have to cast twice (to decimal and back to char), which makes it work:
select ('abc' = convert(convert('abc', decimal(12,2)), char(255)));
returns 0
Thanks.
If you want to examine if the strings are actually floating points numbers, you could also use a regular expression. The following regex can help :)
SELECT '31.23' REGEXP '^[[:digit:]]+([.period.][[:digit:]]+)?$'; # returns 1
SELECT '31' REGEXP '^[[:digit:]]+([.period.][[:digit:]]+)?$'; # returns 1
SELECT 'hey' REGEXP '^[[:digit:]]+([.period.][[:digit:]]+)?$'; # returns 0

Why does this search query return nothing?

I have this table under user_name='high'
function_description :
akram is in a date
test
akram is studying
test4
kheith is male
test3
I want a query that returns results of field that have at least an 'akram'
SELECT *
FROM functions
WHERE 'isEnabled'=1
AND 'isPrivate'=1
AND user_name='high'
AND function_description LIKE '%akram%'
and this returns absolutely nothing!
Why?
You are listing the column names as if they are strings. This is why it returns nothing.
Try this:
SELECT *
FROM functions
WHERE user_name='high'
AND function_description LIKE '%akram%'
edit: After trying to re-read your question... are isEnabled and isPrivate columns in this table?
edit2: updated.. remove those unknown columns.
You are comparing strings 'isEnabled' with integer 1, which likely leads to the integer being converted to a string, and the comparison then fails. (The alternative is that the string is converted to an integer 0 and the comparison still fails.)
In MySQL, you use back-quotes, not single quotes, to quote column and table names:
SELECT *
FROM `functions`
WHERE `isEnabled` = 1
AND `isPrivate` = 1
AND `user_name` = 'high'
AND `function_description` LIKE '%akram%'
In standard SQL, you use double quotes to create a 'delimited identifier'; in Microsoft SQL Server, you use square brackets around the names.
Please show the schema more carefully (column names, sample values, types if need be) next time.

How can I search within a table of comma-separated values?

I have a MySQL table which contains comma-separated values like this:
first row=(3,56,78,12)
second row=(6,44,2,3)
third row=(67,4,2,7,1)
fourth row=(88,55,22,33)
fifth row=(88,55,3,1,5)
I want to select the rows which have 3 in their set. How can I do this?
Try:
SELECT * FROM TABLE_NAME WHERE FIND_IN_SET( 3, COLUMN_NAME )
How about something like
SELECT *
FROM Table
WHERE Field LIKE '3,%'
OR Field LIKE '%,3'
OR Field LIKE '%,3,%'
OR Field = '3'
Just Use Mysql Function FIND_IN_SET(str,strlist) .
Returns a value in the range of 1 to N if the string str is in the string list strlist consisting of N substrings. A string list is a string composed of substrings separated by “,” characters. If the first argument is a constant string and the second is a column of type SET, the FIND_IN_SET() function is optimized to use bit arithmetic. Returns 0 if str is not in strlist or if strlist is the empty string. Returns NULL if either argument is NULL. This function does not work properly if the first argument contains a comma (“,”) character.
SELECT * FROM table_name WHERE FIND_IN_SET('3', column_name);
use this condition
WHERE firstrow LIKE '3,%'
OR firstrow like '%,3'
OR firstrow like '3'
SELECT *
FROM Table
WHERE Field IN ($first_row)
OR Field IN ($second_row)
OR Field IN ($third_row)
OR Field IN ($fourth_row);
you can use IN statement in your query.Please try this.
SELECT *
FROM Table
WHERE Field IN ($first_row)
OR Field IN ($second_row)
OR Field IN ($third_row)
OR Field IN ($fourth_row);