## Question:

Is it possible to convert the following into a two-columned table?```
SELECT * FROM UNNEST([[1,'a'],[2,'b'], [3,'c']) AS tbl (num,str);
```

Or more generally into a table of `n`

columns where `n`

is the size of the inner array (i.e., the length of a row).The array structure is

`arr[rows][cols]`

## Answer:

Arrays in PostgreSQL can contain elements of one type (but it can be composite type). So array like`array[1,2,'e']`

is invalid in PostgreSQL.What can be done is to unnest two arrays in one statement

```
SELECT UNNEST(array[1,2,3]),unnest(array['a','b','c'])
```

If you have better answer, please add a comment about this, thank you!