Examples of org.apache.hadoop.hbase.hbql.filter.SingleColumnValueFilter

org.apache.hadoop.hbase.hbql.filter.SingleColumnValueFilter

This filter is used to filter cells based on value. It takes a {@link org.apache.hadoop.hbase.filter.CompareFilter.CompareOp}operator (equal, greater, not equal, etc), and either a byte [] value or a {@link org.apache.hadoop.hbase.filter.WritableByteArrayComparable}.

If we have a byte [] value then we just do a lexicographic compare. For example, if passed value is 'b' and cell has 'a' and the compare operator is LESS, then we will filter out this cell (return true). If this is not sufficient (eg you want to deserialize a long and then compare it to a fixed long value), then you can pass in your own comparator instead.

You must also specify a family and qualifier. Only the value of this column will be tested.

To prevent the entire row from being emitted if the column is not found on a row, use {@link #setFilterIfMissing}. Otherwise, if the column is found, the entire row will be emitted only if the value passes. If the value fails, the row will be filtered out.

In order to test values of previous versions (timestamps), set {@link #setLatestVersionOnly} to false. The default is true, meaning thatonly the latest version's value is tested and all previous versions are ignored.

To filter based on the value of all scanned columns, use {@link org.apache.hadoop.hbase.filter.ValueFilter}.

    static byte[] val1   = Bytes.toBytes("val1");
    static byte[] val2   = Bytes.toBytes("val2");


    public static void main(String[] args) throws HBqlException, IOException {


        final SingleColumnValueFilter val1Filter11 = new SingleColumnValueFilter(family,
                                                                                 val1,
                                                                                 CompareFilter.CompareOp.EQUAL,
                                                                                 Bytes.toBytes("11"));


        final SingleColumnValueFilter val2Filter10 = new SingleColumnValueFilter(family,
                                                                                 val2,
                                                                                 CompareFilter.CompareOp.EQUAL,
                                                                                 Bytes.toBytes(10));


        doQuery("Results for val2 = 10 || va1l = '11'", val2Filter10, val1Filter11);


        // Bail if expression uses a row key.
        if (attrib.isAKeyAttrib())
            throw new InvalidServerFilterException("Cannot use a key attribute");


        final SingleColumnValueFilter filter = new SingleColumnValueFilter(attrib.getFamilyNameAsBytes(),
                                                                           attrib.getColumnNameAsBytes(),
                                                                           compareOp,
                                                                           comparator);
        filter.setFilterIfMissing(true);
        return filter;
    }

Examples of org.apache.hadoop.hbase.hbql.filter.SingleColumnValueFilter

Related Classes of org.apache.hadoop.hbase.hbql.filter.SingleColumnValueFilter