[HIVE-24538] Enforce strict type checks on all operators relying on comparisons

• Type: Task
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: HiveServer2
• Target Version/s: 4.0.0
• Assignee: Stamatis Zampetakis
• Reporter: Stamatis Zampetakis
• Created: 15/Dec/20 10:22
• Updated: 15/Dec/20 10:23

Description

Strict type checks are enforced when hive.strict.checks.type.safety is enabled to prevent unexpected query results in some common cases where implicit type conversions take place.

At the moment these checks are enforced in most comparison based operators (=,<,>,<=,>=,<>,<=>) but not all. For instance the checks are not active for BETWEEN and IN operators and possibly others. 

The goal of this issue is to review FunctionRegistry#getCommonClassForComparison and make sure that operators relying on comparisons are covered (at a minimum BETWEEN, IN).

Issue Links

• relates to: HIVE-13958 hive.strict.checks.type.safety should apply to decimals, as well as IN... and BETWEEN... ops
• relates to: HIVE-24534 Prevent comparisons between characters and decimals types when strict checks enabled