I have a MySQL table which is as follows:
| id | name | parent_id |
|---|---|---|
| 19 | category1 | 0 |
| 20 | category2 | 19 |
| 21 | category3 | 20 |
| 22 | category4 | 21 |
| … | … | … |
Now, I want to have a single MySQL query to which I simply supply the id [for instance say id=19] then I should get all its child ids [i.e. result should have ids ‘20,21,22’]….
The hierarchy of the children is not known; it can vary….
I know how to do it using a for loop… but how to achieve the same using a single MySQL query?