I'm having a below table called members
+----+--------+--------+-------+--+
| id | name | gender | state | |
+----+--------+--------+-------+--+
| 1 | Peter | M | 1 | |
+----+--------+--------+-------+--+
| 2 | Sally | F | 1 | |
+----+--------+--------+-------+--+
| 3 | Martin | M | 0 | |
+----+--------+--------+-------+--+
Then, my query is
SELECT * FROM `member` WHERE `id` = '1 3';
MySQL returned | 1 | Peter | M | 1 | |.
However, I expect that it would return nothing because there should be no record with id = '1 3'.
How can I prevent this?
Try to use BINARY
select * from member where BINARY id = '1 3';
Related
Update: I want to use dynamic sql to select question as column and put answer in row, like cursor or loop, is that possible?
I want the select result like this
+--------+---------------+--------------------------------------------------------------------------+
| userid | Living Status | This is another question get from row and it's longer than 64 characters |
+--------+---------------+--------------------------------------------------------------------------+
| 19 | married | q2_opt3 |
+--------+---------------+--------------------------------------------------------------------------+
And here is my query
select
userid,
min(if(question.ordering=1,o.name,NULL )) as 'Living Status',
min(if(question.ordering=2,o.name,NULL )) as 'This is another question get from row and it's longer than 64 characters'
from answer
inner join question on question.key_value = answer.key_value
inner join q_option o on question.id = o.question_id and o.value = answer.answer
where userid in (19)
GROUP BY id
The question table is like
+----+----------+---------------------------------------------------------------------------+--------------+
| id | ordering | question | key_value |
+----+----------+---------------------------------------------------------------------------+--------------+
| 1 | 1 | Living Status | livingStatus |
| 2 | 2 | This is another question get from row and it's longer than 64 characters | question_2 |
+----+----------+---------------------------------------------------------------------------+--------------+
The answer table is like
+----+--------+--------------+--------+
| id | answer | key_value | userid |
+----+--------+--------------+--------+
| 1 | 2 | livingStatus | 19 |
| 2 | 3 | question_2 | 19 |
+----+--------+--------------+--------+
The q_option table is like
+----+----------+-------------+-------+
| id | name | question_id | value |
+----+----------+-------------+-------+
| 1 | single | 1 | 1 |
| 2 | married | 1 | 2 |
| 3 | divorced | 1 | 3 |
| 4 | q2_opt1 | 2 | 1 |
| 5 | q2_opt2 | 2 | 2 |
| 6 | q2_opt3 | 2 | 3 |
+----+----------+-------------+-------+
Having that table structure & data:
| ID | PARENT | FIELD_1 | FIELD_2 | RATING |
+------------------------------------------+
| 1 | NULL | F1V1 | F2V1 | 10 |
| 2 | 1 | F1V2 | F2V2 | 20 |
| 3 | 2 | F1V3 | F2V3 | 30 |
| 4 | 3 | F1V4 | F2V4 | 40 |
Is there a way of getting a result like this one:
| ID | F_1 | F_2 | P_F_1 | P_F_2 | G_F_1 | G_F_2 | S_R |
+-------------------------------------------------------------+
| 1 | F1V1 | F2V1 | NULL | NULL | NULL | NULL | 10 |
| 2 | F1V2 | F2V2 | F1V1 | F2V1 | NULL | NULL | 30 |
| 3 | F1V3 | F2V3 | F1V2 | F2V2 | F1V1 | F2V1 | 60 |
| 4 | F1V4 | F2V4 | F1V3 | F2V3 | F1V2 | F2V2 | 90 |
What I actually want, as you can see, is for every record if there are parent (P), grandparent (G), etc records (the recursion may go for 4 levels or any other finite number that is already known), the fields of their ancestors prefixed (that can happen programmatically outside of the query) and a SUM (or any other GROUP function) that calculates the values recursively as well.
ex record #4:
ID = 4
FIELD_1 AS F_1 = F1V4
FIELD_2 AS F_2 = F2V4
PARENT_FIELD_1 AS P_F_1 = F1V3
...
GRANDPARENT_FIELD_2 AS G_F_2 = F2V2
SUM_RATING AS S_M = (40 + 30 + 20) = 90**
NOTE:
Even though record #1 is an ancestor of record #4 (grand-grandparent) its rating is not calculated in the sum because it is not contained in the query.
This simplest way:
SELECT t.id,
t.field_1 f_1,
t.field_2 f_2,
p.field_1 p_f_1,
p.field_2 p_f_2,
g.field_1 g_f_1,
g.field_2 g_f_2,
t.rating + COALESCE(p.rating,0) + COALESCE(g.rating,0) s_r
FROM table_name t
LEFT JOIN table_name p
ON p.id = t.parent
LEFT JOIN table_name g
ON g.id = p.parent
And add left joins, additions and field selections to the known level of recursion.
I would like to join two tables and select from two columns the first one if it is not null, of the other if the first is null. As an example imagine that we have the following tables:
names companies_to_names
-------------------------------- -----------------------------
|id_name | name | nickname | | id | id_name | id_company |
-------------------------------- -----------------------------
| 1 | NULL | manu | | 1 | 1 | 1 |
| 2 | Joe A. | NULL | | 2 | 2 | 1 |
| 3 | Bob B. | NULL | | 3 | 3 | 1 |
| 4 | NULL | alice | | 4 | 4 | 1 |
| 5 | NULL | other | | 5 | 5 | 2 |
-------------------------------- -----------------------------
And we want to show either the name, or the nickname of the guys who work for the company with id=1. Then, I want the following result:
--------------------
|id_name | username|
--------------------
| 1 | manu |
| 2 | Joe A. |
| 3 | Bob B. |
| 4 | alice |
--------------------
I was thinking in SELECT CASE WHEN, but I don't know how to do it. Something like:
SELECT NAMES.id_name CASE username
WHEN NAMES.name IS NULL THEN NAMES.nickname
WHEN NAMES.name IS NOT NULL THEN NAMES.name
END
FROM NAMES INNER JOIN COMPANIES_TO_NAMES ON NAMES.id_name = COMPANIES_TO_NAMES.id_name;
Am I right?
Here is a query that shows you how to solve your problem:
SELECT N.id_name
,IFNULL(N.name, N.nickname) AS [username]
,CASE
WHEN N.name IS NOT NULL THEN 'name'
ELSE 'nickname'
END AS [username_source]
FROM NAMES N
INNER JOIN companies_to_names C ON C.id_name = N.id_name
AND C.id = 1
Hope this will help you.
translations
+---------+----------------+----------+---------+
| id_user | id_translation | referrer | id_word |
+---------+----------------+----------+---------+
| 1 | 3 | NULL | 4 |
| 1 | 17 | NULL | 3 |
| 2 | 17 | NULL | 5 |
| 2 | 17 | NULL | 1 |
| 2 | 17 | NULL | 7 |
words
+----+------+
| id | word |
+----+------+
| 4 | out |
+----+------+
users_translations
+---------+----------------+----------+---------+
| id_user | id_translation | referrer | id_word |
+---------+----------------+----------+---------+
| 1 | 17 | 1 | 4 |
| 2 | 17 | 2 | 4 |
| 3 | 18 | NULL | 4 |
I need to select all translations for current word and id_translation, but if in the row referrer = 1 (current user), then I don't need another results (translations from another users for current word), if there is no referrer = 1, show all.
SELECT DISTINCT `t`.*, `ut`.`id_user` AS tuser
FROM translations AS t
LEFT JOIN users_translations AS ut ON `t`.`id` = `ut`.`id_translation`
INNER JOIN words ON `words`.`id` = `ut`.`id_word` OR `words`.`id` = `t`.`id_word`
WHERE (`word` = 'help')
ORDER BY `t`.`translation` ASC
+----+-------------+---------+---------+-------+
| id | translation | id_word | id_user | tuser |
+----+-------------+---------+---------+-------+
| 17 | допомагати | 4 | 1 | 2 |
| 17 | допомагати | 4 | 1 | 1 |
First row doesn't need, because we have tuser = 1. When there is no tuser = 1, all results should be returned.
I don't understand how to build select statement and I will be very appreciative that somebody shows me how to make it work.
First thing that comes to mind
--add this to your where clause
id_user <=
CASE WHEN EXISTS(SELECT * FROM translations WHERE id_user = 1 AND id_word = words.id_word)
THEN 1
ELSE (SELECT MAX(Id) FROM translations)
END
I have two tables that look like this:
Table A:
+-----+-----+------+-------+
| aID | uID | attr | value |
+-----+-----+------+-------+
| 1 | 1 | fn | john |
+-----+-----+------+-------+
| 2 | 1 | ln | smith |
+-----+-----+------+-------+
| 3 | 2 | fn | jim |
+-----+-----+------+-------+
| 4 | 2 | ln | bean |
+-----+-----+------+-------+
Table B:
+-----+-----+-------+-------+
| bID | uID | perm | value |
+-----+-----+-------+-------+
| 1 | 1 | admin | 1 |
+-----+-----+-------+-------+
| 2 | 2 | news | 1 |
+-----+-----+-------+-------+
| 3 | 2 | cms | 1 |
+-----+-----+-------+-------+
As it shows, Table A holds attribute data for a user uID, and Table B holds permission data for a user uID.
At the moment, I am using,:
SELECT GROUP_CONCAT(`a`.`attr`) AS `attrs`
, GROUP_CONCAT(`a`.`value`) AS `values`
, GROUP_CONCAT(`b`.`perm`) AS `perms`
FROM `a`
JOIN `b`
ON `a`.`uID` = `b`.`uID`
GROUP BY `a`.`uID`, `b`.`uID`
But it is giving me a result:
+-------------+-------------------+-------------------+
| attrs | values | perms |
+-------------+-------------------+-------------------+
| fn,ln | John,Smith | admin,admin |
+-------------+-------------------+-------------------+
| fn,fn,ln,ln | Jim,Jim,Bean,Bean | news,cms,news,cms |
+-------------+-------------------+-------------------+
What do I need to change in my query to get:
+-------+------------+----------+
| attrs | values | perms |
+-------+------------+----------+
| fn,ln | John,Smith | admin |
+-------+------------+----------+
| fn,fn | Jim,Bean | news,cms |
+-------+------------+----------+
GROUP_CONCAT takes additional arguments, as explained on its documentation page here.
The one you want is distinct:
SELECT GROUP_CONCAT(distinct `a`.`attr`) AS `attrs` . . .