Question

I have two tables in my SQL database:

mysql> select *from crop;
+------+-----------+----------+
| no   | name      | type     |
+------+-----------+----------+
| 1    | pineapple | fruits   |
| 2    | wheat     | mainFood |
| 1    | apple     | fruits   |
| 2    | corn      | main     |
| 3    | rose      | flower   |
| 2    | wheat     | main     |
| 2    | maize     | main     |
| 1    | drydates  | fruits   |
+------+-----------+----------+

mysql> select *from enviornment;
+---------+------------+----------+------+
| climate | irrigation | soil     | no   |
+---------+------------+----------+------+
| humid   | medium     | alluvial | 2    |
| humid   | medium     | black    | 1    |
| humid   | medium     | red      | 1    |
| sunny   | low        | black    | 1    |
| sunny   | medium     | alluvial | 1    |
| wet     | high       | red      | 2    |
| humid   | low        | red      | 3    |
+---------+------------+----------+------+

I want to get the name and type fields from the crop table, based on climate, soil, and irrigation.

I have written my query in the following way:

mysql> select T.name from((select name from crop)as T and (select no from envior
nment where climate like wet)as U)where T.no=U.no;

But when I try to execute it, I get the following error:

ERROR 1064 (42000): 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 (select no from enviornment where climate like wet)as U)where T.no=U.no’ at line 1

Can anyone tell me how to re-write my query to avoid this error?

Answer 1

You cannot use AND to construct query-results, it’s a logical operator. You can get all name, type, climate, soil and irrigation combinations with:

select c.name, c.type, e.climate, e.soil, e.irrigation
from crop c, environment e
where c.no = e.no;