String getDataType(ParserRuleContext ctx, String conn, String column) {
    String type = null;
    HashMap<String, Row> map = dataTypes.get(conn);
    if (map == null) {
      map = new HashMap<String, Row>();
      dataTypes.put(conn, map);
    }
    ArrayList<String> twoparts = splitIdentifierToTwoParts(column);
    if (twoparts != null) {
      String tab = twoparts.get(0);
      String col = twoparts.get(1).toUpperCase();
      Row row = map.get(tab);
      if (row != null) {
        type = row.getType(col);
      }
      else {
        row = readColumns(ctx, conn, tab, map);
        if (row != null) {
          type = row.getType(col);
        }
      }
    }
    return type;
  }
Get the data type of column (column name is qualified i.e. schema.table.column)
hplsql/src/main/java/org/apache/hive/hplsql/Meta.java