[HIVE-2249] When creating constant expression for numbers, try to infer type from another comparison operand, instead of trying to use integer first, and then long and double

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.9.0
• Assignee: Zhiqiu Kong
• Reporter: Siying Dong
• Created: 30/Jun/11 23:43
• Updated: 16/Aug/24 15:08
• Resolved: 31/Jan/12 06:40

Description

The current code to build constant expression for numbers, here is the code:

try

{ v = Double.valueOf(expr.getText()); v = Long.valueOf(expr.getText()); v = Integer.valueOf(expr.getText()); }

catch (NumberFormatException e)

{ // do nothing here, we will throw an exception in the following block }

if (v == null)

{ throw new SemanticException(ErrorMsg.INVALID_NUMERICAL_CONSTANT .getMsg(expr)); }

return new ExprNodeConstantDesc(v);

The for the case that "WHERE <BIG_INT_COLUMN> = 0", or "WHERE <DOUBLE_COLUMN> = 0", we always have to do a type conversion when comparing, which is unnecessary if it is slightly smarter to choose type when creating the constant expression. We can simply walk one level up the tree, find another comparison party and use the same type with that one if it is possible. For user's wrong query like '<INT_COLUMN>=1.1', we can even do more.

Issue Links

• is related to: HIVE-28449 Infer constant types from columns before strict type validation
• relates to: HIVE-2586 Float comparison doesn't work