When I execute this query with MATCH AGAINST using MySql (see Query 1st) the issue in this query they has generated an error like this (see error) or when I execute the same query with = they executed normally(see Query 2nd).
My question is what am I doing wrong with against statement?
Query 1st
SELECT (SELECT COUNT(up.`user_id`)
FROM `users_post` up WHERE MATCH (up.`user_id`) AGAINST (uf.`user_id`))
AS user_count
FROM `users` uf
Error
enter code hereError Code : 1210
Incorrect arguments to AGAINST
(0 ms taken)
Update
Query 2nd
SELECT
(SELECT COUNT(up.`user_id`)
FROM `users_post` up WHERE up.`user_id` = uf.`user_id`)
AS user_count
FROM `users` uf
The problem is that the argument for AGAINST must be a literal string, for example 'Fred'. It is not allowed to use a column name like uf.user_id.
MATCH (up.`user_id`) AGAINST (uf.`user_id`)
-- ^^^^^^^^^^^^ not allowed!
From the documentation:
The search string must be a literal string, not a variable or a column name.
You probably need to use LIKE instead of MATCH, though you should note that it will be much slower.
Related
I am new to COALESCE function in REDSHIFT. I ran below four queries in mysql and Redshift.
1st and 2nd query executed as expected in both mysql and redshift. But for 3rd and 4th query I am getting two different results in mysql and Redshift. How does this behave?
select COALESCE(null,null,1) -> 1
select COALESCE(null,null,'John') -> 1
select COALESCE(null,null,1,'John') -> (Redshift : error , mysql:1)
select COALESCE(null,null,'John',1) -> (Redshift: error, mysql:John)
Also this query should give error in mysql but it has succeeded
Any help is appreciated
Amazon Redshift Database Developer Guide claims:
An NVL expression is identical to a COALESCE expression. NVL and
COALESCE are synonyms.
Syntax
NVL | COALESCE ( expression, expression, ... )
An NVL or COALESCE expression returns the value of the first expression
in the list that is not null. If all expressions are null, the result
is null. When a non-null value is found, the remaining expressions in
the list are not evaluated.
This type of expression is useful when you want to return a backup
value for something when the preferred value is missing or null. For
example, a query might return one of three phone numbers (cell, home,
or work, in that order), whichever is found first in the table (not
null).
If you obtain the error this may mean that the returned value datatype do not match the datatype of recordset field or any another structure which must accept the returned value.
PS. Will you show error messages?
Though it is not written in the documentation, but coalesce works on the compatible data types. Integer and varchar cannot be compared.
The error becomes more evident when you provide column name instead of hard-code values. Try executing this:
select coalesce(integer_column, varchar_column) from a_table;
You would get an error saying something like this:
coalesce types integer and varchar cannot be matched.
I have used below mysql query for fetching data:
select *
from tableName
where tableName.field_type='22'
and tableName.field_id NOT LIKE(select aField_id
from TableName 02 where status !='Active')
I am getting error
1242 - Subquery returns more than 1 row
can you let me know what wrong in this query
select * from tableName
where tableName.field_type='22'
and
tableName.field_id
NOT IN(select aField_id from TableName where status !='Active')
Use not in in place of not like. Not in is for comparison of column with a set of values. not like is for comparison of column with a single value or pattern. Your subquery in returning more than one rows. not like can't handle that.
Like deals with only one input. So you should use IN in place of LIKE.
I have the table Exceptions where a row with column named [Value] equals the string Ceakcacohkka. When running the query:
SELECT * FROM Exceptions WHERE Value='Čeakčačohkka'
The above mentioned row is returned. SQL Server somehow ignores the special chars and matches this [Value] to the string provided.
If I change the string to Čeakčačohkka the same select statement returns no rows!
How is this possible? Something with international settings?
This case is similar to: S.O Question; mySQL returns all rows when field=0, and the Accepted answer was a very simple trick, to souround the ZERO with single quotes
FROM:
SELECT * FROM table WHERE email=0
TO:
SELECT * FROM table WHERE email='0'
However, my case is slightly different in that my Query is something like:
SELECT * FROM table WHERE email=(
SELECT my_column_value FROM myTable WHERE my_column_value=0 AND user_id =15 LIMIT 1 )
Which in a sense, becomes like simply saying: SELECT * FROM table WHERE email=0, but now with a Second Query.
PLEASE NOTE: It is a MUST that I use the SECOND QUERY.
When I tried: SELECT * FROM table WHERE email='( SELECT my_column_value FROM myTable WHERE my_column_value=0 LIMIT 1 )' (Notice the Single Quotes on the second query)
MySql SCREAMED Errors near '(.
How can this be achieved
Any Suggestion is highly honored
EDIT1: For a visual perspective of the Query
See the STEN_TB here: http://snag.gy/Rq8dq.jpg
Now, the main aim is to get the sten_h where rawscore_h = 0;
The CURRENT QUERY as a whole.
SELECT sten_h
FROM sten_tb
WHERE rawscore_h = (
SELECT `for_print_stens_rowscore`
FROM `for_print_stens_tb`
WHERE `for_print_stens_student_id` =3
AND `for_print_stens_factor_name` = 'Factor H' )
The result of the Second Query can be any number including ZERO.
Any number from >=1 Works and returns a single corresponding value from sten_h. Only =0 does not Work, it returns all rows
That's the issue.
CORRECT ANSWER OR SOLUTION FOR THIS
Just in case someone ends up in this paradox, the Accepted answer has it all.
SEE STEN_TB: http://snag.gy/Rq8dq.jpg
SEE The desired Query result here: http://snag.gy/wa4yA.jpg
I believe your issue is with implicit datatype conversions. You can make those datatype conversions explicit, to gain control.
(The "trick" with wrapping a literal 0 in single quotes, that makes the literal a string literal, rather than a numeric.)
In the more general case, you can use a CAST or CONVERT function to explicitly specify a datatype conversion. You can use an expression in place of a column name, wherever you need to...
For example, to get the value returned by my_column_value to match the datatype of the email column, assuming email is character type, something like:
... email = (SELECT CONVERT(my_column_value,CHAR(255)) FROM myTable WHERE ...
or, to get the a literal integer value to be a string value:
... FROM myTable WHERE my_column_value = CONVERT(0,CHAR(30)) ...
If email and my_column_value are just indicating true or false then they should almost certainly be both BIT NOT NULL or other two-value type that your schema uses for booleans. (Your ORM may use a particular one.) Casting is frequently a hack made necessary by a poor design.
If it should be a particular user then you shouldn't use LIMIT because tables are unordered and that doesn't return a particular user. Explain in your question what your query is supposed to return including exactly what you mean by "15th".
(Having all those similar columns is bad design: rawscore_a, sten_a, rawscore_b, sten_b,... . Use a table with two columns: rawscore, sten.)
I'm trying to run a SQL SELECT statement against a column that is of type SET. The table is called myTable and the columns in myTable are called base_props and names. The base_props column is of type SET. The values in base_prop are vb,nt, cnt,poss and loc. So I would like to SELECT entries from the column 'name' where base_props have both the values, vb and poss. The results I'm looking to get may have values other than just vb and poss. So to be clear I would like to select all entries that have the values vb and poss regardless if they have other values as well. I've tried the following SQL queries but I can't get the desired results.
SELECT name from myTable WHERE base_props = 'vb' AND base_props = 'poss'
That query returns an empty result set. I've tried using FIND_IN_SET() and IN() but I couldn't get anywhere with that. I've written SQL statements before but never had to deal with columns that are type SET. Any help is appreciated.
The only thing I can come up with is using the LIKE keyword:
SELECT name FROM myTable WHERE (base_props LIKE '%vb%' AND base_props LIKE '%poss%');
This will make sure both vb and cnt are in the base_props column. Of course you can use cnt, nt and loc in there, or any number of base_props values in the sql, just add more AND statements.
OR as a deleted answer by samitha pointed out, you can use FIND_IN_SET:
SELECT name from myTable WHERE FIND_IN_SET('vb', base_props) AND FIND_IN_SET('poss', base_props);
Comment (by spencer7593): "both of these work, but there is a slight difference. The LIKE operator will actually match any member that includes the search string anywhere in a term; the FIND_IN_SET function will only match an exact member. It's also possible to search for members in set by the order they appear in the SET definition, using the MySQL BITAND operator: for example, to match the 1st and 4th members of the set: WHERE base_props & 1 AND base_props & 8". So for example, if you have 'a' and 'aaa' in your set, then using the LIKE "%a%" method will also return rows containing 'aaa'.
Conclusion: use the FIND_IN_SET solution since it will work for all cases.
FIND_IN_SET return index, Try this
SELECT name from myTable WHERE FIND_IN_SET(base_props, 'vb') > 0 AND
FIND_IN_SET(base_props, 'poss') > 0