Question: Hello I am a beginner at SQL, especially postgresql. 
I have a table that looks something like this:

```
ID    | Entity   | Startdate | enddate
------| ------   | ------    | ------ 
1     | Hospital |2013-01-01 |2013-01-31
1     | Clinic   |2013-02-01 |2013-04-30
1     | Hospital |2013-05-01 |2013-05-31

```

What I would like to do in this case is that where the start and end date span more than a month to break it out so the above table would like this: 

```
ID    | Entity   | Startdate | enddate
------| ------   | ------    | ------
1     | Hospital |2013-01-01 |2013-01-31
1     | Clinic   |2013-02-01 |2013-02-29
1     | Clinic   |2013-03-01 |2013-03-31
1     | Clinic   |2013-04-01 |2013-04-30
1     | Hospital |2013-05-01 |2013-05-31

```

If you notice that row 2, 3 and 4 have been broken down by the month and the ID and entity have also been duplicated. 

Any suggestions on how to run this in postgresql would be appreciated. 

P.S Apologies I am trying to figure out how to create the table above properly. Having difficulty, the pipes between the numbers and words are lines in a table. 
Hope its not too confusing.

Answer: 
> 
> Any idea why firefox changes the value of the attribute?
> 
> 
> 

Because `middle` *is* the correct value as defined in [RFC 1866 (HTML 2.0)](https://www.rfc-editor.org/rfc/rfc1866#page-35), [HTML 3.2](https://www.w3.org/TR/REC-html32#img) and [HTML 4](https://www.w3.org/TR/html4/struct/objects.html#h-13.7.4), not `center`. The `align` attribute on the `img` element has never had `center` as a possible value, because `center` has historically always referred to horizontal alignment (floating), and you can't float an image at the center of a line. Other implementations at the time, such as IE, *did* allow `center` as a possible value with the same meaning as `middle` (see Stefan's answer), and so my guess is that Firefox is providing interop while still adhering to the standard by aliasing the values.

It's not clear to me why Chrome doesn't do the same. It does seem to treat `center` as `middle` for the purposes of rendering, in any case. But if by rewriting the value Firefox is breaking attribute selectors, I'd consider that a defect (albeit one they probably aren't inclined to fix since the attribute is obsolete).

The real question is why [MDN claims](https://developer.mozilla.org/en/docs/Web/API/HTMLImageElement) that the only possible values are `left`, `right`, `justify`, and `center`. The [DOM level 2 spec](https://www.w3.org/TR/DOM-Level-2-HTML/html.html#ID-17701901), of course, contains a more accurate description of the `align` attribute, though it doesn't list the possible values since they're already listed in the HTML spec.
the [html specification](https://www.w3.org/TR/html401/struct/objects.html#adef-align-IMG) does not know of a value *center* for the align attribute for img tags (but for other tags). however, firefox probably recognizes *center* as value (instead of other nonsense) and accepts it as *middle* since firefox and possible other browsers have done this at some point in their life according to this [rather ancient bug report](https://bugzilla.mozilla.org/show_bug.cgi?id=192077)