Process abort when reaching internal limit for subselect materialization
Details
| Detail name | Value |
|---|---|
| Changelog Number | 6814 |
| Type | Bug |
| Status | Resolved |
| Affected Versions | EXASOL 6.0.8 |
| Fix Versions | Exasol 6.1.0 |
| Resolution Date | 2018-11-19 |
Background
During any statement, Exasol may create intermediate materializations of subselects for efficient processing. Internally, there is a limit for the number of those materializations per statement.
For very large and complex queries, that require a large number of intermediate materialization steps, eventually this limit may be reached.
Problem
Reaching this limit causes an internal server error.
How to reproduce
Create a large query with around 30000 sub-queries that require materialization.
Fix
Starting with 6.0.13, a proper exception will be returned: "internal limit, too complex execution pipeline".
