All Questions
3 questions
0
votes
1
answer
241
views
"ON UPDATE" in self referencing table
I have a table Category with a parent_id column referencing the self id column, for this, I used "ON DELETE CASCADE" meaning if the parent is deleted, other children would be deleted too.
At ...
- 23
-2
votes
1
answer
55
views
ON DELETE / ON UPDATE doubts
I was looking at database past exam from the school that I attend, and I have a question about ON DELETE and ON UPDATE.
The question in the past exam was:
Show the contents of the tables after ...
- 15
1
vote
1
answer
312
views
Remove accidental duplicates in PK table, cascade changes to FK table
Lets say I have three tables in a postgreSQL database, one of plants, one of samples, and one of mappings to change variables in plants. There is a PK-FK relationship between plants.id and samples....
- 193