Github user jackylk commented on a diff in the pull request:
https://github.com/apache/carbondata/pull/2519#discussion_r203245324
--- Diff:
core/src/main/java/org/apache/carbondata/core/datamap/DataMapChooser.java ---
@@ -269,6 +270,12 @@ private void extractColumnExpression(Expression
expression,
List<ColumnExpression> columnExpressions) {
if (expression instanceof ColumnExpression) {
columnExpressions.add((ColumnExpression) expression);
+ } else if (expression instanceof MatchExpression) {
+ // fake ColumnExpression for lucene. normal query string is alike
"column:query term"
--- End diff --
please describe what is the use of this fake ColumnExpression.
And it is better to mention `Lucene query string` instead of `normal query
string`
---
