Tagged Questions
0
votes
1answer
9 views
JOIN to read first table and get possible relationship in the second table
Consider a main table as
CREATE TABLE groups
(
group_id int(11) NOT NULL AUTO_INCREMENT,
group_title varchar(255),
PRIMARY KEY(group_id)
) ENGINE=InnoDB
and a second table for relationship as
...
2
votes
3answers
230 views
Express union which is dependent on other results
I would like to make a union of two tables that are actually in a hierarchical constellation.
How would I write that in relational algebra? Say table A is the parent of B in a 1:n relationship.
...
