SQL: Syntax error - mysql

I am executing this query in MySql:
SELECT amount
FROM Prices
WHERE (item_id = 1246 AND
('2016-12-26' BETWEEN (effective_date AND COALESCE(end_date, NOW()))))
But for some reason I get a syntax error that I don't see where it is.
the error is:
You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ')) AND(item_id = 1419 AND ('2017-01-14' BETWEEN (effective_date AND COALESCE(end' at line 1
the Price is like this:
Prices
id
item_id
effective_date
end_date

I don't think there should be parentheses between BETWEEN and the first term of that expression. Something like this should work:
SELECT amount
FROM Prices
WHERE item_id = 1246 AND
'2016-12-26' BETWEEN effective_date AND COALESCE(end_date, NOW())
This question is a typo, but maybe this answer would be useful to anyone who wants to know the proper way to use BETWEEN.
The MySQL documentation for BETWEEN doesn't explicitly mention anything about parentheses, but it seems to be implying this based on the examples given.
Based on testing this locally, parentheses around each of the two terms in the BETWEEN expression are OK, e.g.
WHERE '2016-12-26' BETWEEN (effective_date) AND (COALESCE(end_date, NOW()))
However, putting parenthesis around the entire clause generates an error, which is what you were doing:
WHERE '2016-12-26' BETWEEN (effective_date AND COALESCE(end_date, NOW()))

Related

MySQL: Ordering of columns when using a wildcard with group by has odd behavior

What is the difference between these two MySQL statements?
Works:
select *, count(mycol) c from mytable group by mycol;
Doesn't work:
select count(mycol) c, * from mytable group by mycol;
The first statement works as I'd expect, while the second one gives me a syntax error. Why does the order matter?
I'm having trouble finding an answer from Google, because I'm not entirely sure if I'm asking the question correctly.
Edit:
Here's the sanitized error message. I'm using MySQL Workbench, if that's relevant.
Error Code: 1064. You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '* from mytable group by id' at line 1
Just alias the table and the syntax error will go away.
select count(t.id) c, t.* from mytable t group by id;
See this db fiddle.
It looks like MySQL allows bare (unqualified) * only as immediatly following SELECT. The following query also raises a syntax error :
select 1, * from mytable t;
The documentation prevents against using bare * combined with other items in the SELECT list :
A select list consisting only of a single unqualified * can be used as shorthand to select all columns from all tables.
Use of an unqualified * with other items in the select list may produce a parse error. To avoid this problem, use a qualified tbl_name.* reference.

MySQL - Using * in a conditional statement

I am attempting to execute the following statement...
SELECT
SUM(CASE WHEN CLG ='A*' THEN 1 END) as A*
From Grades
However, I receive the following error...
"You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '*,"
I realise of course that * is used in select statements to select all the rows of a table. However in my case, I want to find the number of records that contain the value of A*. Would anyone be able to point out what I can do to solve this error without having to remove the A* values from my table?
You need to use backticks:
SELECT SUM(CASE WHEN CLG ='A*' THEN 1 END) as `A*`
From Grades;
Actually you could skip CASE:
SELECT SUM(CLG ='A*') as `A*`
From Grades
Your problem is the column alias. Don't use inappropriate characters for column names. Do something like this:
SELECT SUM( CLG = 'A*' ) as A_star
From Grades;
Having to deal with identifiers that use unusual characters is just a pain -- making queries hard to write and to read.

Select COUNT (*) fails if no result

I'm trying to do a simple query (below) to see if there are no rows found in a table. If there are none, then do something.
SELECT COUNT (*) as count FROM AT_vbc_content_status
However, I keep getting this error...
You have an error in your SQL syntax; check the manual that
corresponds to your MySQL server version for the right syntax to use
near '*) as count FROM [name of my table] WHERE member_id= '16'' at
line 1
Where am I going wrong?
You have to remove the space between COUNT and (
COUNT(*)
Remove the space between COUNT and the parenthesis like this: COUNT(*)
See the MySQL documentation at the link below for explanation
http://dev.mysql.com/doc/refman/5.1/en/function-resolution.html
The MySql function is COUNT(field_name) and there must not be any space between COUNT and (*), So Remove the extra space between COUNT and (*)
$content_status_sql = "SELECT COUNT(*) as count FROM AT_vbc_content_status WHERE member_id= '".$_SESSION['member_id']."'";

does the existence of an asterisk in a select exclude other columns?

This question is all about laziness... I'd like to do something like this:
select some_func(some_col), * from my_table
So that I don't have to do this:
select some_func(some_col), col_1, col_2... col_ad_infinitum from my_table
Is there any way to make the first query work? This is the error I get when I run it:
ERROR 1064 (42000) at line 1: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '* from my_table' at line 1
Do you mean that in MySQL your first query:
SELECT some_func(some_col), *
FROM my_table
produces this error?:
Error Code: 1064. You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '*' at line 1
You can change your code into (this results in no errors!):
SELECT *, some_func(some_col)
FROM my_table
or into this, if you want to have the calculated columns first:
SELECT some_func(some_col), t.*
FROM my_table AS t
Unfortunately, mysql only supports the asterisk at the start of the column list (unlike every other DB I am familiar with)
(Edited: start not end - oops!)
Change the order of your select params:
select *,some_func(some_col) from my_table
Anyway, as the Zen of Python says: "Explicit is better than implicit". Always try to write the fields you're selecting, and if it's posible try to put the table they're from too, you can use an alias. Your future YOU will thank you.
select t.some_col from my_table t
When I do that with PostgreSQL, I get the column(s) I specify followed by all the other columns (possibly repeating the column(s) I specified).

MySQL and average of multiple columns

I need to return average for each of 12 columns I have in a table in DB. MySQL allows one to get average for one column only. The following query (for one column) works:
SELECT station_id, AVG(jan) AS avg_jan
FROM `climate_data`
WHERE element_name = "Temp_mean_mly" AND jan <> -999999
GROUP BY station_id
and the following (for multiple columns) does not (I get syntax error):
SELECT station_id, AVG(jan) AS avg_jan, AVG(feb) AS avg_feb, ... ,
AVG(dec) AS avg_dec
FROM `climate_data`
WHERE element_name = "Temp_mean_mly"
AND jan <> -999999
AND feb <> -999999
AND ...
AND dec <> -999999
GROUP BY station_id
Do I have to use 12 sub-queries to achieve the result I need?
1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'dec)
dec is a reserved MySQL keyword; changing it to `dec` in your query would probably fix that error for you :).
Edit: note that you're also using it in the WHERE clause; it might work there (as it's unlogical for MySQL to find a keyword there), but keep it in mind that you might also have to escape that one :)