[Isthmus][SQLExpression] Produce projection/filter extended expressions with predefined column names #229
Description
The aim of this enhancement is to produce projection/filter extended expressions with predefined column names. The SQL Expression currently generates column names using the format column-[0...n]
Current:
new SqlExpressionToSubstrait().convert(new String[]{"N_REGIONKEY + 10", "N_NATIONKEY > 18"}, ...);
Produce:
column-1 column-2
23 false
30 true
Proposal:
new SqlExpressionToSubstrait().convert(new String[]{"N_REGIONKEY + 10", "N_NATIONKEY > 18"},
new String[]{"key_10", "key_18"}, ...);
Produce:
key_10 key_18
23 false
30 true