1.move PushdownFilterThroughCTEAnchor and PushdownProjectThroughCTEAnchor into PUSH_DOWN_FILTERS rule set
2.move PushdownFilterThroughProject before MergeProjectPostProcessor
This pr contribute:
- support explain CTE;
- refine CTE, fix the bug: reuse the same analyzed plan which LogicalOlapScan has the same relationId;
- change EliminateAliasNode to LogicalSubQueryAliasToLogicalProject and move to the top of rewrite stage, so we can simply observe the analyzed plan by the LogicalSubQueryAlias with alias;
- job traverse left child first, so the ExprId growth from left child to right child.
Support common table expression(CTE) in Nereids:
- Just implemented inline CTE, which means we will copy the logicalPlan of CTE everywhere it is referenced;
- If the name of CTE is the same as an existing table or view, we will choose CTE first;