[CALCITE-205] Suspicious map.get in VolcanoPlanner.reregister

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Labels: github-import
• Assignee: Unassigned
• Reporter: GitHub Import
• Created: 18/Jun/14 08:36
• Updated: 18/Jun/14 08:36
• Resolved: 18/Jun/14 08:36

Description

Here is rather strange `map.get` since it never returns a match:
https://github.com/julianhyde/optiq/blob/ddc6aca8bc76080b5c396a605a0be148aa0a2d79/core/src/main/java/org/eigenbase/relopt/volcano/VolcanoPlanner.java#L1253

I tried to convert it to `equivRel = map.get(Pair.of(rel.getDigest(), rel.getRowType()))`, however it never manages to enter into `if (equivRel != null && equivRel != rel)` (typically, `equivRel == rel`)

Can you please double-check if this mapDigestToRel is required here?

```java
Map<Pair<String, RelDataType>, RelNode> mapDigestToRel
...
// Is there an equivalent relational expression? (This might have
// just occurred because the relational expression's child was just
// found to be equivalent to another set.)
RelNode equivRel = mapDigestToRel.get(rel.getDigest());
if ((equivRel != null) && (equivRel != rel)) {
```

---------------- Imported from GitHub ----------------
Url: https://github.com/julianhyde/optiq/issues/205
Created by: vlsi
Labels: bug,
Created at: Tue Mar 25 07:44:34 CET 2014
State: closed