Examples of GroupBy

cascading.pipe.GroupBy
The GroupBy pipe groups the {@link Tuple} stream by the given groupFields.
If more than one {@link Pipe} instance is provided on the constructor, all branches will be merged. It is requiredthat all Pipe instances output the same field names, otherwise the {@link cascading.flow.FlowConnector} will fail to create a{@link cascading.flow.Flow} instance. Again, the Pipe instances are merged together as if one Tuple stream and not joined.See {@link CoGroup} for joining by common fields.
Typically an {@link Every} follows GroupBy to apply an {@link Aggregator} function to every grouping. The{@link Each} operator may also follow GroupBy to apply a {@link Function} or {@link Filter} to the resultingstream. But an Each cannot come immediately before an Every.
Optionally a stream can be further sorted by providing sortFields. This allows an Aggregator to receive values in the order of the sortedFields.
Note that local sorting always happens on the groupFields, sortFields are a secondary sorting on the grouped values within the current grouping. sortFields is particularly useful if the Aggregators following the GroupBy would like to see their arguments in order.
For more control over sorting at the group or secondary sort level, use {@link cascading.tuple.Fields}containing {@link java.util.Comparator} instances for the appropriate fields when setting the groupFields orsortFields values. Fields allows you to set a custom {@link java.util.Comparator} instance for each field name orposition. It is required that each Comparator class also be {@link java.io.Serializable}.
It should be noted for MapReduce systems, distributed group sorting is not 'total'. That is groups are sorted as seen by each Reducer, but they are not sorted across Reducers. See the MapReduce algorithm for details.
See the {@link cascading.tuple.Hasher} interface when a custom {@link java.util.Comparator} on the grouping keys isbeing provided that makes two values with differing hashCode values equal. For example, {@code new BigDecimal( 100.0D )} and {@code new Double 100.0D )} are equal using a custom Comparator, but{@link Object#hashCode()} will be different, thus forcing each value into differing partitions.
Note that grouping one String key with a lowercase value with another String key with an uppercase value using a "case insensitive" Comparator will not have consistent results. The grouping will execute and be correct, but the actual values in the key columns may be replaced with "equivalent" values from other streams.
That is, if two streams are merged and then grouped on a key, where one stream the key values are uppercase and the other stream values are lowercase, the resulting key value for the grouping may arbitrarily be either upper or lower case.
If the original key values must be retained, consider normalizing the keys with a Function and then grouping on the resulting field.
co.nubetech.crux.model.GroupBy
com.odiago.flumebase.parser.GroupBy
GROUP BY clause attached to a SELECT statement.
com.salesforce.phoenix.compile.GroupByCompiler.GroupBy
org.apache.phoenix.compile.GroupByCompiler.GroupBy
org.codehaus.jparsec.examples.sql.ast.GroupBy
"group by" clause. @author Ben Yu
org.springframework.data.mongodb.core.mapreduce.GroupBy
Collects the parameters required to perform a group operation on a collection. The query condition and the input collection are specified on the group method as method arguments to be consistent with other operations, e.g. map-reduce. @author Mark Pollack
org.teiid.language.GroupBy
Represents a GROUP BY clause in a query.
org.teiid.query.sql.lang.GroupBy
This class represents the GROUP BY clause of a query, which defines the expressions that should be used for grouping the results of the query. The groups produced in the query are grouped on all symbols listed contained in the GROUP BY clause. The GROUP BY clause may not contain aliased elements, expressions, or constants.
org.twodividedbyzero.idea.findbugs.gui.tree.GroupBy

Examples of org.apache.phoenix.compile.GroupByCompiler.GroupBy

        if (table.getViewStatement() != null) {
            viewWhere = new SQLParser(table.getViewStatement()).parseQuery().getWhere();
        }
        Integer limit = LimitCompiler.compile(context, select);


        GroupBy groupBy = GroupByCompiler.compile(context, select);
        // Optimize the HAVING clause by finding any group by expressions that can be moved
        // to the WHERE clause
        select = HavingCompiler.rewrite(context, select, groupBy);
        Expression having = HavingCompiler.compile(context, select, groupBy);
        // Don't pass groupBy when building where clause expression, because we do not want to wrap these

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Examples of org.apache.phoenix.compile.GroupByCompiler.GroupBy

        if (tableRef.getTable().getType() == PTableType.INDEX && tableRef.getTable().getIndexState() != PIndexState.ACTIVE) {
            return new DegenerateQueryPlan(context, select, tableRef);
        }
        Integer limit = LimitCompiler.compile(context, select);


        GroupBy groupBy = GroupByCompiler.compile(context, select);
        // Optimize the HAVING clause by finding any group by expressions that can be moved
        // to the WHERE clause
        select = HavingCompiler.rewrite(context, select, groupBy);
        Expression having = HavingCompiler.compile(context, select, groupBy);
        // Don't pass groupBy when building where clause expression, because we do not want to wrap these

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Examples of org.apache.phoenix.compile.GroupByCompiler.GroupBy

        PhoenixConnection pconn = DriverManager.getConnection(getUrl(), TEST_PROPERTIES).unwrap(PhoenixConnection.class);
        ColumnResolver resolver = FromCompiler.getResolver(statement, pconn);
        statement = StatementNormalizer.normalize(statement, resolver);
        context = new StatementContext(statement, pconn, resolver, binds, scan);


        GroupBy groupBy = GroupByCompiler.compile(context, statement);
        // Optimize the HAVING clause by finding any group by expressions that can be moved
        // to the WHERE clause
        statement = HavingCompiler.rewrite(context, statement, groupBy);
        Expression having = HavingCompiler.compile(context, statement, groupBy);
        Expression where = WhereCompiler.compile(context, statement);

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Examples of org.apache.phoenix.compile.GroupByCompiler.GroupBy

        statement = StatementNormalizer.normalize(statement, resolver);
        StatementContext context = new StatementContext(statement, pconn, resolver, binds, scan);


        Integer actualLimit = LimitCompiler.compile(context, statement);
        assertEquals(limit, actualLimit);
        GroupBy groupBy = GroupByCompiler.compile(context, statement);
        statement = HavingCompiler.rewrite(context, statement, groupBy);
        WhereCompiler.compileWhereClause(context, statement, extractedNodes);
        return context;
    }

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Examples of org.apache.phoenix.compile.GroupByCompiler.GroupBy

        ColumnResolver resolver = FromCompiler.getResolver(statement, pconn);
        statement = StatementNormalizer.normalize(statement, resolver);
        StatementContext context = new StatementContext(statement, pconn, resolver, binds, scan);


        Integer limit = LimitCompiler.compile(context, statement);
        GroupBy groupBy = GroupByCompiler.compile(context, statement);
        statement = HavingCompiler.rewrite(context, statement, groupBy);
        HavingCompiler.compile(context, statement, groupBy);
        Expression where = WhereCompiler.compile(context, statement);
        assertNull(where);
        return limit;

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Examples of org.apache.phoenix.compile.GroupByCompiler.GroupBy

        statement = StatementNormalizer.normalize(statement, resolver);
        StatementContext context = new StatementContext(statement, pconn, resolver, binds, scan);


        Integer actualLimit = LimitCompiler.compile(context, statement);
        assertEquals(limit, actualLimit);
        GroupBy groupBy = GroupByCompiler.compile(context, statement);
        statement = HavingCompiler.rewrite(context, statement, groupBy);
        WhereCompiler.compileWhereClause(context, statement, extractedNodes);
        return context;
    }

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Examples of org.apache.phoenix.compile.GroupByCompiler.GroupBy

        if (table.getViewStatement() != null) {
            viewWhere = new SQLParser(table.getViewStatement()).parseQuery().getWhere();
        }
        Integer limit = LimitCompiler.compile(context, select);


        GroupBy groupBy = GroupByCompiler.compile(context, select);
        // Optimize the HAVING clause by finding any group by expressions that can be moved
        // to the WHERE clause
        select = HavingCompiler.rewrite(context, select, groupBy);
        Expression having = HavingCompiler.compile(context, select, groupBy);
        // Don't pass groupBy when building where clause expression, because we do not want to wrap these

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Examples of org.codehaus.jparsec.examples.sql.ast.GroupBy

        new AliasedRelation(table("table1"), "t1"), table("t2"));
  }
  
  public void testGroupByClause() {
    Parser<GroupBy> parser = RelationParser.groupByClause(NUMBER, NUMBER);
    assertParser(parser, "group by 1, 2", new GroupBy(Arrays.asList(number(1), number(2)), null));
    assertParser(parser, "group by 1, 2 having 3",
        new GroupBy(Arrays.asList(number(1), number(2)), number(3)));
  }

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Examples of org.codehaus.jparsec.examples.sql.ast.GroupBy

            number(1), null, null));
    assertParser(parser, "select 1 as id from t group by 2, 3",
        new Select(false, 
            Arrays.asList(new Projection(number(1), "id")),
            Arrays.asList(table("t")),
            null, new GroupBy(Arrays.asList(number(2), number(3)), null), null));
    assertParser(parser, "select 1 as id from t group by 2, 3 having 4",
        new Select(false, 
            Arrays.asList(new Projection(number(1), "id")),
            Arrays.asList(table("t")),
            null, new GroupBy(Arrays.asList(number(2), number(3)), number(4)), null));
    assertParser(parser, "select 1 as id from t order by 2 asc, 3 desc",
        new Select(false, 
            Arrays.asList(new Projection(number(1), "id")),
            Arrays.asList(table("t")),
            null, null, new OrderBy(Arrays.asList(

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Examples of org.codehaus.jparsec.examples.sql.ast.GroupBy

  }


  @Test
  public void testGroupByClause() {
    Parser<GroupBy> parser = RelationParser.groupByClause(NUMBER, NUMBER);
    assertParser(parser, "group by 1, 2", new GroupBy(Arrays.asList(number(1), number(2)), null));
    assertParser(parser, "group by 1, 2 having 3",
        new GroupBy(Arrays.asList(number(1), number(2)), number(3)));
  }

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