json可以包含相同的键值吗？

I take the content of two table performing a join like this:

SELECT * FROM table1
     INNER JOIN table2
     ON table1.code = table2.code

Now the table1 have a structure like this:

|CODE|Info|Created          |Modified
|R789|Home|21/03/2016 10:00 |21/03/2016 15:00

and table2:

|CODE|Description|Created       |Modified
|R789|Testing| 21/03/2016 10:05 | 21/03/2016  18:10

Now the problem is that the query return this result:

"Code":"RB01",
"Info":Home,
"Created":"21/03/2016 10:05",
"Modified":"21/03/2016 18:10",
"Description":"Testing"

How you can see I have createdand modified that is identical in the two tables. So the query discard the created and modified of table1.. this is a problem for me, how can I avoid this situation?

You need to use the AS keyword to create an alias for the column name. Consider this:

SELECT t1.CODE, t1.Info, t1.Created AS t1Created, t1.Modified AS t1Modified, t2.Description, t2.Created AS t2Created, t2.Modified AS t2Modified
    FROM table1 t1
    INNER JOIN table2 t2 ON t1.CODE = t2.CODE

This will return

"Code":"RB01",
"Info":Home,
"t1Created":"21/03/2016 10:00",
"t1Modified":"21/03/2016 15:00",
"Description":"Testing",
"t2Created":"21/03/2016 10:05",
"t2Modified":"21/03/2016 18:10",