Examples with RowSchema org.apache.hadoop.hive.ql.exec.RowSchema used on opensource projects

Example 76 with RowSchema

use of org.apache.hadoop.hive.ql.exec.RowSchema in project hive by apache.

the class SemanticAnalyzer method genInputSelectForUnion.

/**
   * Generates a select operator which can go between the original input operator and the union
   * operator. This select casts columns to match the type of the associated column in the union,
   * other columns pass through unchanged. The new operator's only parent is the original input
   * operator to the union, and it's only child is the union. If the input does not need to be
   * cast, the original operator is returned, and no new select operator is added.
   *
   * @param origInputOp
   *          The original input operator to the union.
   * @param origInputFieldMap
   *          A map from field name to ColumnInfo for the original input operator.
   * @param origInputAlias
   *          The alias associated with the original input operator.
   * @param unionoutRR
   *          The union's output row resolver.
   * @param unionalias
   *          The alias of the union.
   * @return
   * @throws SemanticException
   */
private Operator<? extends OperatorDesc> genInputSelectForUnion(Operator<? extends OperatorDesc> origInputOp, Map<String, ColumnInfo> origInputFieldMap, String origInputAlias, RowResolver unionoutRR, String unionalias) throws SemanticException {
    HashMap<String, ColumnInfo> fieldMap = unionoutRR.getFieldMap(unionalias);
    Iterator<ColumnInfo> oIter = origInputFieldMap.values().iterator();
    Iterator<ColumnInfo> uIter = fieldMap.values().iterator();
    List<ExprNodeDesc> columns = new ArrayList<ExprNodeDesc>();
    boolean needsCast = false;
    while (oIter.hasNext()) {
        ColumnInfo oInfo = oIter.next();
        ColumnInfo uInfo = uIter.next();
        ExprNodeDesc column = new ExprNodeColumnDesc(oInfo.getType(), oInfo.getInternalName(), oInfo.getTabAlias(), oInfo.getIsVirtualCol(), oInfo.isSkewedCol());
        if (!oInfo.getType().equals(uInfo.getType())) {
            needsCast = true;
            column = ParseUtils.createConversionCast(column, (PrimitiveTypeInfo) uInfo.getType());
        }
        columns.add(column);
    }
    // If none of the columns need to be cast there's no need for an additional select operator
    if (!needsCast) {
        return origInputOp;
    }
    RowResolver rowResolver = new RowResolver();
    Map<String, ExprNodeDesc> columnExprMap = new HashMap<String, ExprNodeDesc>();
    List<String> colName = new ArrayList<String>();
    for (int i = 0; i < columns.size(); i++) {
        String name = getColumnInternalName(i);
        ColumnInfo col = new ColumnInfo(name, columns.get(i).getTypeInfo(), "", false);
        rowResolver.put(origInputAlias, name, col);
        colName.add(name);
        columnExprMap.put(name, columns.get(i));
    }
    Operator<SelectDesc> newInputOp = OperatorFactory.getAndMakeChild(new SelectDesc(columns, colName), new RowSchema(rowResolver.getColumnInfos()), columnExprMap, origInputOp);
    return putOpInsertMap(newInputOp, rowResolver);
}