
Say you're looking at a MySQL integer column where some rows are null:

```sql
select
  day,
  tickets
from stats;
```

```
    day     | tickets
------------+-------
 2018-01-01 |     1
 2018-01-02 |   null
 2018-01-03 |     3
```

Instead of having that null, you might want that row to be `0`. To do that, use the `ifnull` function, which returns the first non-null argument it's passed:

```sql
select
  day,
  ifnull(tickets, 0)
from stats;
```

```
    day     | tickets
------------+-------
 2018-01-01 |     1
 2018-01-02 |     0
 2018-01-03 |     3
```


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