property JoinTables: TLzJoinList;
Joins in from clause. Join is represented by class TLzJoin.
Usually, Join count in from is 1.
/* ANSI join */
SELECT emp_lname, emp_fname, job_title
FROM employee
JOIN jobs ON employee.job_id = jobs.job_id;
But in the "old" way to do join operations,Theta joins, which use the WHERE clause to establish the filtering criteria, join count is the number of table in from clause.
/* Theta join */
SELECT emp_lname, emp_fname, job_title
FROM employee, jobs
WHERE employee.job_id = jobs. job_id;
Join count in this from clause is 2.
TlzJoinList
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