1 Hint Classification

1.1 Leading Hint：Specifies the join order according to the order provided in the leading hint.
1.2 Ordered Hint：A specific type of leading hint that specifies the join order as the original text sequence.
1.3 Distribute Hint：Specifies the data distribution method for joins as either shuffle or broadcast.
1.4 CBO Rules
1.4.1 CBO rule control hints

2 Hint Log

2.1 usage and log

explain shape plan select  /*+ leading(t2 t1) */