public static Expression normalizeExpression(Expression expression) {
    return new ExpressionNormalizeVisitor(true).process(expression, null);
  }
Remove view and measurement alias from expression, and reconstruct the name of
FunctionExpression to lowercase.

@return normalized expression
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/queryengine/plan/analyze/ExpressionAnalyzer.java