I am trying to work with a two (already) generated tables. In one table 1 there is a column named column_code
In table 2 the columns are named like the data in column_code
Per example Table 1:
meta_data
----------------------------------
| pid | 1 |
| question | favorite website |
| column_code | AA123ZZ |
----------------------------------
where column_code
has a content named: 'AA123ZZ'
and question is called: what is your favorite website
Table 2:
content
-----------------------------------
| id | 4 |
| submit_date | 14-01-2013 |
| AA123ZZ | stackoverflow.com |
-----------------------------------
The content of this table_name AA123ZZ
is for instance " stackoverflow.com "
Now what I want is a query where the result will be something like:
id: = 1
what is your favorite website: stackoverflow.com
So actually AA123ZZ
stands for this question, I have no other way of matching these together, how can I do this?
I am sorry I cannot make this any clearer. I got these two tables and indeed they seem to be missing something.
In the content table the table name AA123ZZ
is 'code' for the question.
The maker of the database should just have placed the question as column name in stead of this code AA123ZZ
. Now I need to match this code to what is inside meta_data
.
So in meta_data in the question_column you can find: "favorite website" and in the column_code
you will find AA123ZZ
.
in the content table in the AA123ZZ
column you will find: stackoverflow.com
As you can see I cannot match these easily on a inner join.
So is there a way to match a column_name from one table to the contents of a column in another table?
You can't join tables where the column name
itself is variable. You're going to need to fix the schema here, perhaps to include a foreign key
value to the meta_data
table from the content
table and from there you can do a simple join
on the two tables.
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