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A fork of the Apache Cassandra Project ready to embed Elasticsearch.
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
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* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.cassandra.cql3;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import java.util.TreeSet;
import org.apache.cassandra.config.CFMetaData;
import org.apache.cassandra.config.ColumnDefinition;
import org.apache.cassandra.cql3.restrictions.SingleColumnRestriction;
import org.apache.cassandra.cql3.restrictions.SingleRestriction;
import org.apache.cassandra.cql3.restrictions.TermSlice;
import org.apache.cassandra.cql3.selection.Selection;
import org.apache.cassandra.cql3.statements.Bound;
import org.apache.cassandra.db.Clustering;
import org.apache.cassandra.db.Columns;
import org.apache.cassandra.db.CompactTables;
import org.apache.cassandra.db.PartitionColumns;
import org.apache.cassandra.db.filter.ColumnFilter;
import org.apache.cassandra.db.filter.RowFilter;
import org.apache.cassandra.db.marshal.AbstractType;
import org.apache.cassandra.db.marshal.MapType;
import org.apache.cassandra.db.marshal.UTF8Type;
import org.apache.cassandra.db.rows.Cell;
import org.apache.cassandra.db.rows.CellPath;
import org.apache.cassandra.db.rows.ComplexColumnData;
import org.apache.cassandra.db.rows.Row;
import org.apache.cassandra.db.rows.RowIterator;
import org.apache.cassandra.transport.ProtocolVersion;
import org.apache.cassandra.utils.ByteBufferUtil;
import org.apache.cassandra.utils.FBUtilities;
import org.apache.cassandra.utils.Pair;
import static org.apache.cassandra.cql3.statements.RequestValidations.checkFalse;
import static org.apache.cassandra.cql3.statements.RequestValidations.checkNotNull;
import static org.apache.cassandra.cql3.statements.RequestValidations.checkTrue;
import static org.apache.cassandra.cql3.statements.RequestValidations.invalidRequest;
import static org.apache.cassandra.cql3.statements.SelectStatement.getComponents;
/**
* Class incapsulating the helper logic to handle SELECT / UPDATE / INSERT special-cases related
* to SuperColumn tables in applicable scenarios.
*
* SuperColumn families have a special layout and are represented as a Map internally. These tables
* have two special columns (called `column2` and `value` by default):
*
* * `column2`, {@link CFMetaData#superCfValueColumn}, a key of the SuperColumn map, exposed as a
* REGULAR column, but stored in schema tables as a CLUSTERING column to make a distinction from
* the SC value column in case of renames.
* * `value`, {@link CFMetaData#compactValueColumn()}, a value of the SuperColumn map, exposed and
* stored as a REGULAR column
*
* These columns have to be translated to this internal representation as key and value, correspondingly.
*
* In CQL terms, the SuperColumn families is encoded with:
*
* CREATE TABLE super (
* key [key_validation_class],
* super_column_name [comparator],
* [column_metadata_1] [type1],
* ...,
* [column_metadata_n] [type1],
* "" map<[sub_comparator], [default_validation_class]>
* PRIMARY KEY (key, super_column_name)
* )
*
* In other words, every super column is encoded by a row. That row has one column for each defined
* "column_metadata", but it also has a special map column (whose name is the empty string as this is
* guaranteed to never conflict with a user-defined "column_metadata") which stores the super column
* "dynamic" sub-columns.
*
* On write path, `column2` and `value` columns are translated to the key and value of the
* underlying map. During the read, the inverse conversion is done. Deletes are converted into
* discards by the key in the underlying map. Counters are handled by translating an update to a
* counter update with a cell path. See {@link SuperColumnRestrictions} for the details.
*
* Since non-dense SuperColumn families do not modify the contents of the internal map through in CQL
* and do not expose this via CQL either, reads, writes and deletes are handled normally.
*
* Sidenote: a _dense_ SuperColumn Familiy is the one that has no added REGULAR columns.
*/
public class SuperColumnCompatibility
{
// We use an empty value for the 1) this can't conflict with a user-defined column and 2) this actually
// validate with any comparator which makes it convenient for columnDefinitionComparator().
public static final ByteBuffer SUPER_COLUMN_MAP_COLUMN = ByteBufferUtil.EMPTY_BYTE_BUFFER;
public static final String SUPER_COLUMN_MAP_COLUMN_STR = UTF8Type.instance.compose(SUPER_COLUMN_MAP_COLUMN);
/**
* Dense flag might have been incorrectly set if the node was upgraded from 2.x before CASSANDRA-12373.
*
* For 3.x created tables, the flag is set correctly in ThriftConversion code.
*/
public static boolean recalculateIsDense(Columns columns)
{
return columns.size() == 1 && columns.getComplex(0).name.toString().isEmpty();
}
/**
* For _dense_ SuperColumn Families, the supercolumn key column has to be translated to the collection subselection
* query in order to avoid reading an entire collection and then filtering out the results.
*/
public static ColumnFilter getColumnFilter(CFMetaData cfm, QueryOptions queryOptions, SuperColumnRestrictions restrictions)
{
assert cfm.isSuper() && cfm.isDense();
ColumnFilter.Builder builder = ColumnFilter.selectionBuilder();
builder.add(cfm.compactValueColumn());
if (restrictions.keySliceRestriction != null)
{
SingleColumnRestriction.SuperColumnKeySliceRestriction restriction = restrictions.keySliceRestriction;
TermSlice slice = restriction.slice;
ByteBuffer start = slice.hasBound(Bound.START) ? slice.bound(Bound.START).bindAndGet(queryOptions) : null;
ByteBuffer end = slice.hasBound(Bound.END) ? slice.bound(Bound.END).bindAndGet(queryOptions) : null;
builder.slice(cfm.compactValueColumn(),
start == null ? CellPath.BOTTOM : CellPath.create(start),
end == null ? CellPath.TOP : CellPath.create(end));
}
else if (restrictions.keyEQRestriction != null)
{
SingleColumnRestriction.SuperColumnKeyEQRestriction restriction = restrictions.keyEQRestriction;
ByteBuffer value = restriction.bindValue(queryOptions);
builder.select(cfm.compactValueColumn(), CellPath.create(value));
}
else if (restrictions.keyINRestriction != null)
{
SingleColumnRestriction.SuperColumnKeyINRestriction cast = restrictions.keyINRestriction;
Set keyINRestrictionValues = new TreeSet(((MapType) cfm.compactValueColumn().type).getKeysType());
keyINRestrictionValues.addAll(cast.getValues(queryOptions));
for (ByteBuffer value : keyINRestrictionValues)
builder.select(cfm.compactValueColumn(), CellPath.create(value));
}
else if (restrictions.multiEQRestriction != null)
{
SingleColumnRestriction.SuperColumnMultiEQRestriction restriction = restrictions.multiEQRestriction;
ByteBuffer value = restriction.secondValue;
builder.select(cfm.compactValueColumn(), CellPath.create(value));
}
return builder.build();
}
/**
* For _dense_ SuperColumn Families.
*
* On read path, instead of writing row per map, we have to write a row per key/value pair in map.
*
* For example:
*
* | partition-key | clustering-key | { key1: value1, key2: value2 } |
*
* Will be translated to:
*
* | partition-key | clustering-key | key1 | value1 |
* | partition-key | clustering-key | key2 | value2 |
*
*/
public static void processPartition(CFMetaData cfm, Selection selection, RowIterator partition, Selection.ResultSetBuilder result, ProtocolVersion protocolVersion,
SuperColumnRestrictions restrictions, QueryOptions queryOptions)
{
assert cfm.isDense();
ByteBuffer[] keyComponents = getComponents(cfm, partition.partitionKey());
int nowInSeconds = FBUtilities.nowInSeconds();
while (partition.hasNext())
{
Row row = partition.next();
ComplexColumnData ccd = row.getComplexColumnData(cfm.compactValueColumn());
if (ccd == null)
continue;
Iterator cellIter = ccd.iterator();
outer:
while (cellIter.hasNext())
{
Cell cell = cellIter.next();
ByteBuffer superColumnKey = cell.path().get(0);
if (restrictions != null)
{
// Slice on SuperColumn key
if (restrictions.keySliceRestriction != null)
{
for (Bound bound : Bound.values())
{
if (restrictions.keySliceRestriction.hasBound(bound) &&
!restrictions.keySliceRestriction.isInclusive(bound))
{
ByteBuffer excludedValue = restrictions.keySliceRestriction.bindValue(queryOptions);
if (excludedValue.equals(superColumnKey))
continue outer;
}
}
}
// Multi-column restriction on clustering+SuperColumn key
if (restrictions.multiSliceRestriction != null &&
cfm.comparator.compare(row.clustering(), Clustering.make(restrictions.multiSliceRestriction.firstValue)) == 0)
{
AbstractType t = ((MapType) cfm.compactValueColumn().type).getKeysType();
int cmp = t.compare(superColumnKey, restrictions.multiSliceRestriction.secondValue);
if ((cmp == 0 && !restrictions.multiSliceRestriction.trueInclusive) || // EQ
(restrictions.multiSliceRestriction.hasBound(Bound.END) && cmp > 0) || // LT
(restrictions.multiSliceRestriction.hasBound(Bound.START) && cmp < 0)) // GT
continue outer;
}
}
Row staticRow = partition.staticRow();
result.newRow(partition.partitionKey(), staticRow.clustering());
for (ColumnDefinition def : selection.getColumns())
{
if (cfm.isSuperColumnKeyColumn(def))
{
result.add(superColumnKey);
}
else if (cfm.isSuperColumnValueColumn(def))
{
result.add(cell, nowInSeconds);
}
else
{
switch (def.kind)
{
case PARTITION_KEY:
result.add(keyComponents[def.position()]);
break;
case CLUSTERING:
result.add(row.clustering().get(def.position()));
break;
case REGULAR:
case STATIC:
throw new AssertionError(String.format("Invalid column '%s' found in SuperColumn table", def.name.toString()));
}
}
}
}
}
}
/**
* For _dense_ SuperColumn Families.
*
* On the write path, we have to do combine the columns into a key/value pair:
*
* So inserting a row:
*
* | partition-key | clustering-key | key1 | value1 |
*
* Would result into:
*
* | partition-key | clustering-key | {key1: value1} |
*
* or adding / overwriting the value for `key1`.
*/
public static void prepareInsertOperations(CFMetaData cfm,
List columnNames,
WhereClause.Builder whereClause,
List columnValues,
VariableSpecifications boundNames,
Operations operations)
{
List defs = new ArrayList<>(columnNames.size());
for (int i = 0; i < columnNames.size(); i++)
{
ColumnDefinition id = columnNames.get(i).prepare(cfm);
defs.add(id);
}
prepareInsertOperations(cfm, defs, boundNames, columnValues, whereClause, operations);
}
/**
* For _dense_ SuperColumn Families.
*
* {@link #prepareInsertOperations(CFMetaData, List, VariableSpecifications, List, WhereClause.Builder, Operations)},
* but for INSERT JSON queries
*/
public static void prepareInsertJSONOperations(CFMetaData cfm,
List defs,
VariableSpecifications boundNames,
Json.Prepared prepared,
WhereClause.Builder whereClause,
Operations operations)
{
List columnValues = new ArrayList<>(defs.size());
for (ColumnDefinition def : defs)
columnValues.add(prepared.getRawTermForColumn(def, true));
prepareInsertOperations(cfm, defs, boundNames, columnValues, whereClause, operations);
}
private static void prepareInsertOperations(CFMetaData cfm,
List defs,
VariableSpecifications boundNames,
List columnValues,
WhereClause.Builder whereClause,
Operations operations)
{
assert cfm.isDense();
assert defs.size() == columnValues.size();
Term.Raw superColumnKey = null;
Term.Raw superColumnValue = null;
for (int i = 0, size = defs.size(); i < size; i++)
{
ColumnDefinition def = defs.get(i);
Term.Raw raw = columnValues.get(i);
if (cfm.isSuperColumnKeyColumn(def))
{
superColumnKey = raw;
collectMarkerSpecifications(raw, boundNames, def);
}
else if (cfm.isSuperColumnValueColumn(def))
{
superColumnValue = raw;
collectMarkerSpecifications(raw, boundNames, def);
}
else if (def.isPrimaryKeyColumn())
{
whereClause.add(new SingleColumnRelation(ColumnDefinition.Raw.forColumn(def), Operator.EQ, raw));
}
else
{
throw invalidRequest("Invalid column {} in where clause");
}
}
checkTrue(superColumnValue != null,
"Column value is mandatory for SuperColumn tables");
checkTrue(superColumnKey != null,
"Column key is mandatory for SuperColumn tables");
Operation operation = new Operation.SetElement(superColumnKey, superColumnValue).prepare(cfm, cfm.compactValueColumn());
operations.add(operation);
}
/**
* Collect the marker specifications for the bound columns manually, since the operations on a column are
* converted to the operations on the collection element.
*/
private static void collectMarkerSpecifications(Term.Raw raw, VariableSpecifications boundNames, ColumnDefinition def)
{
if (raw instanceof AbstractMarker.Raw)
boundNames.add(((AbstractMarker.Raw) raw).bindIndex(), def);
}
/**
* For _dense_ SuperColumn Families.
*
* During UPDATE operation, the update by clustering (with correponding relation in WHERE clause)
* has to be substituted with an update to the map that backs the given SuperColumn.
*
* For example, an update such as:
*
* UPDATE ... SET value = 'value1' WHERE key = 'pk' AND column1 = 'ck' AND column2 = 'mk'
*
* Will update the value under key 'mk' in the map, backing the SuperColumn, located in the row
* with clustering 'ck' in the partition with key 'pk'.
*/
public static WhereClause prepareUpdateOperations(CFMetaData cfm,
WhereClause whereClause,
List> updates,
VariableSpecifications boundNames,
Operations operations)
{
assert cfm.isDense();
Term.Raw superColumnKey = null;
Term.Raw superColumnValue = null;
List newRelations = new ArrayList<>(whereClause.relations.size());
for (int i = 0; i < whereClause.relations.size(); i++)
{
SingleColumnRelation relation = (SingleColumnRelation) whereClause.relations.get(i);
ColumnDefinition def = relation.getEntity().prepare(cfm);
if (cfm.isSuperColumnKeyColumn(def))
{
superColumnKey = relation.getValue();
collectMarkerSpecifications(superColumnKey, boundNames, def);
}
else
{
newRelations.add(relation);
}
}
checkTrue(superColumnKey != null,
"Column key is mandatory for SuperColumn tables");
for (Pair entry : updates)
{
ColumnDefinition def = entry.left.prepare(cfm);
if (!cfm.isSuperColumnValueColumn(def))
throw invalidRequest("Column `%s` of type `%s` found in SET part", def.name, def.type.asCQL3Type());
Operation operation;
if (entry.right instanceof Operation.Addition)
{
Operation.Addition op = (Operation.Addition) entry.right;
superColumnValue = op.value();
operation = new Operation.ElementAddition(superColumnKey, superColumnValue).prepare(cfm, cfm.compactValueColumn());
}
else if (entry.right instanceof Operation.Substraction)
{
Operation.Substraction op = (Operation.Substraction) entry.right;
superColumnValue = op.value();
operation = new Operation.ElementSubtraction(superColumnKey, superColumnValue).prepare(cfm, cfm.compactValueColumn());
}
else if (entry.right instanceof Operation.SetValue)
{
Operation.SetValue op = (Operation.SetValue) entry.right;
superColumnValue = op.value();
operation = new Operation.SetElement(superColumnKey, superColumnValue).prepare(cfm, cfm.compactValueColumn());
}
else
{
throw invalidRequest("Invalid operation `%s` on column `%s` of type `%s` found in SET part", entry.right, def.name, def.type.asCQL3Type());
}
collectMarkerSpecifications(superColumnValue, boundNames, def);
operations.add(operation);
}
checkTrue(superColumnValue != null,
"Column value is mandatory for SuperColumn tables");
return newRelations.size() != whereClause.relations.size() ? whereClause.copy(newRelations) : whereClause;
}
/**
* Rebuilds LWT conditions on SuperColumn _value_ column.
*
* Conditions have to be changed to correspond the internal representation of SuperColumn value, since it's not
* a separate column, but a value in a hidden compact value column.
*/
public static Conditions rebuildLWTColumnConditions(Conditions conditions, CFMetaData cfm, WhereClause whereClause)
{
if (conditions.isEmpty() || conditions.isIfExists() || conditions.isIfNotExists())
return conditions;
ColumnConditions.Builder builder = ColumnConditions.newBuilder();
Collection columnConditions = ((ColumnConditions) conditions).columnConditions();
Pair superColumnKeyRelation = SuperColumnCompatibility.getSuperColumnKeyRelation(whereClause.relations, cfm);
checkNotNull(superColumnKeyRelation,
"Lightweight transactions on SuperColumn tables are only supported with supplied SuperColumn key");
for (ColumnCondition columnCondition : columnConditions)
{
checkTrue(cfm.isSuperColumnValueColumn(columnCondition.column),
"Lightweight transactions are only supported on the value column of SuperColumn tables");
Term.Raw value = superColumnKeyRelation.right.getValue();
Term collectionElemnt = value instanceof AbstractMarker.Raw ?
new Constants.Marker(((AbstractMarker.Raw) value).bindIndex(),
superColumnKeyRelation.left) :
value.prepare(cfm.ksName, superColumnKeyRelation.left);
builder.add(ColumnCondition.condition(cfm.compactValueColumn(),
collectionElemnt,
columnCondition.value(), columnCondition.operator));
}
return builder.build();
}
/**
* Returns a relation on the SuperColumn key
*/
private static Pair getSuperColumnKeyRelation(List relations, CFMetaData cfm)
{
for (int i = 0; i < relations.size(); i++)
{
SingleColumnRelation relation = (SingleColumnRelation) relations.get(i);
ColumnDefinition def = relation.getEntity().prepare(cfm);
if (cfm.isSuperColumnKeyColumn(def))
return Pair.create(def, relation);
}
return null;
}
/**
* For _dense_ SuperColumn Families.
*
* Delete, when the "regular" columns are present, have to be translated into
* deletion of value in the internal map by key.
*
* For example, delete such as:
*
* DELETE FROM ... WHERE key = 'pk' AND column1 = 'ck' AND column2 = 'mk'
*
* Will delete a value under 'mk' from the map, located in the row with clustering key 'ck' in the partition
* with key 'pk'.
*/
public static WhereClause prepareDeleteOperations(CFMetaData cfm,
WhereClause whereClause,
VariableSpecifications boundNames,
Operations operations)
{
assert cfm.isDense();
List newRelations = new ArrayList<>(whereClause.relations.size());
for (int i = 0; i < whereClause.relations.size(); i++)
{
Relation orig = whereClause.relations.get(i);
checkFalse(orig.isMultiColumn(),
"Multi-column relations cannot be used in WHERE clauses for UPDATE and DELETE statements: %s", orig);
checkFalse(orig.onToken(),
"Token relations cannot be used in WHERE clauses for UPDATE and DELETE statements: %s", orig);
SingleColumnRelation relation = (SingleColumnRelation) orig;
ColumnDefinition def = relation.getEntity().prepare(cfm);
if (cfm.isSuperColumnKeyColumn(def))
{
Term.Raw value = relation.getValue();
if (value instanceof AbstractMarker.Raw)
boundNames.add(((AbstractMarker.Raw) value).bindIndex(), def);
Operation operation = new Maps.DiscarderByKey(cfm.compactValueColumn(), value.prepare(cfm.ksName, def));
operations.add(operation);
}
else
{
newRelations.add(relation);
}
}
return newRelations.size() != whereClause.relations.size() ? whereClause.copy(newRelations) : whereClause;
}
/**
* Create a column name generator for SuperColumns
*/
public static CompactTables.DefaultNames columnNameGenerator(List partitionKeyColumns,
List clusteringColumns,
PartitionColumns partitionColumns)
{
Set names = new HashSet<>();
// If the clustering column was renamed, the supercolumn key's default nname still can't be `column1` (SuperColumn
// key renames are handled separately by looking up an existing column).
names.add("column1");
for (ColumnDefinition columnDefinition: partitionKeyColumns)
names.add(columnDefinition.name.toString());
for (ColumnDefinition columnDefinition: clusteringColumns)
names.add(columnDefinition.name.toString());
for (ColumnDefinition columnDefinition: partitionColumns)
names.add(columnDefinition.name.toString());
return CompactTables.defaultNameGenerator(names);
}
/**
* Find a SuperColumn key column if it's available (for example, when it was renamed) or create one with a default name.
*/
public static ColumnDefinition getSuperCfKeyColumn(CFMetaData cfm, List clusteringColumns, CompactTables.DefaultNames defaultNames)
{
assert cfm.isDense();
MapType mapType = (MapType) cfm.compactValueColumn().type;
// Pre CASSANDRA-12373 3.x-created supercolumn family
if (clusteringColumns.size() == 1)
{
// create a new one with a default name
ColumnIdentifier identifier = ColumnIdentifier.getInterned(defaultNames.defaultClusteringName(), true);
return new ColumnDefinition(cfm.ksName, cfm.cfName, identifier, mapType.getKeysType(), ColumnDefinition.NO_POSITION, ColumnDefinition.Kind.REGULAR);
}
// Upgrade path: table created in 2.x, handle pre-created columns and/or renames.
assert clusteringColumns.size() == 2 : clusteringColumns;
ColumnDefinition cd = clusteringColumns.get(1);
assert cd.type.equals(mapType.getKeysType()) : cd.type + " != " + mapType.getKeysType();
return new ColumnDefinition(cfm.ksName, cfm.cfName, cd.name, mapType.getKeysType(), ColumnDefinition.NO_POSITION, ColumnDefinition.Kind.REGULAR);
}
/**
* Find a SuperColumn value column if it's available (for example, when it was renamed) or create one with a default name.
*/
public static ColumnDefinition getSuperCfValueColumn(CFMetaData cfm, PartitionColumns partitionColumns, ColumnDefinition superCfKeyColumn, CompactTables.DefaultNames defaultNames)
{
assert cfm.isDense();
MapType mapType = (MapType) cfm.compactValueColumn().type;
for (ColumnDefinition def: partitionColumns.regulars)
{
if (!def.name.bytes.equals(SUPER_COLUMN_MAP_COLUMN) && def.type.equals(mapType.getValuesType()) && !def.equals(superCfKeyColumn))
return def;
}
ColumnIdentifier identifier = ColumnIdentifier.getInterned(defaultNames.defaultCompactValueName(), true);
return new ColumnDefinition(cfm.ksName, cfm.cfName, identifier, mapType.getValuesType(), ColumnDefinition.NO_POSITION, ColumnDefinition.Kind.REGULAR);
}
/**
* SuperColumn key is stored in {@link CFMetaData#columnMetadata} as a clustering column (to make sure we can make
* a distinction between the SuperColumn key and SuperColumn value columns, especially when they have the same type
* and were renamed), but exposed as {@link CFMetaData#superCfKeyColumn} as a regular column to be compatible with
* the storage engine.
*
* This remapping is necessary to facilitate the column metadata part.
*/
public static ColumnDefinition getSuperCfSschemaRepresentation(ColumnDefinition superCfKeyColumn)
{
return new ColumnDefinition(superCfKeyColumn.ksName, superCfKeyColumn.cfName, superCfKeyColumn.name, superCfKeyColumn.type, 1, ColumnDefinition.Kind.CLUSTERING);
}
public static boolean isSuperColumnMapColumn(ColumnDefinition column)
{
return column.isRegular() && column.name.bytes.equals(SuperColumnCompatibility.SUPER_COLUMN_MAP_COLUMN);
}
public static ColumnDefinition getCompactValueColumn(PartitionColumns columns)
{
for (ColumnDefinition column : columns.regulars)
{
if (isSuperColumnMapColumn(column))
return column;
}
throw new AssertionError("Invalid super column table definition, no 'dynamic' map column");
}
/**
* Restrictions are the trickiest part of the SuperColumn integration.
* See specific docs on each field. For the purpose of this doc, the "default" column names are used,
* `column2` and `value`. Detailed description and semantics of these fields can be found in this class'
* header comment.
*/
public static class SuperColumnRestrictions
{
/**
* Restrictions in the form of:
* ... AND (column1, column2) > ('value1', 1)
* Multi-column restrictions. `column1` will be handled normally by the clustering bounds,
* and `column2` value has to be "saved" and filtered out in `processPartition`, as there's no
* direct mapping of multi-column restrictions to clustering + cell path. The first row
* is special-cased to make sure the semantics of multi-column restrictions are preserved.
*/
private final SingleColumnRestriction.SuperColumnMultiSliceRestriction multiSliceRestriction;
/**
* Restrictions in the form of:
* ... AND (column1, column2) = ('value1', 1)
* Multi-column restriction with EQ does have a direct mapping: `column1` will be handled
* normally by the clustering bounds, and the `column2` will be special-cased by the
* {@link #getColumnFilter(CFMetaData, QueryOptions, SuperColumnRestrictions)} as a collection path lookup.
*/
private final SingleColumnRestriction.SuperColumnMultiEQRestriction multiEQRestriction;
/**
* Restrictions in the form of:
* ... AND column2 >= 5
* For non-filtering cases (when the preceding clustering column and a partition key are
* restricted), will be handled in {@link #getColumnFilter(CFMetaData, QueryOptions, SuperColumnRestrictions)}
* like an inclusive bounds lookup.
*
* For the restrictions taking a form of
* ... AND column2 > 5
* (non-inclusive ones), the items that match `=` will be filtered out
* by {@link #processPartition(CFMetaData, Selection, RowIterator, Selection.ResultSetBuilder, ProtocolVersion, SuperColumnRestrictions, QueryOptions)}
*
* Unfortunately, there are no good ways to do it other than here:
* {@link RowFilter} can't be used in this case, since the complex collection cells are not yet rows by that
* point.
* {@link ColumnFilter} (which is used for inclusive slices) can't be changed to support exclusive slices as it would
* require a protocol change in order to add a Kind. So exclusive slices are a combination of inclusive plus
* an ad-hoc filter.
*/
private final SingleColumnRestriction.SuperColumnKeySliceRestriction keySliceRestriction;
/**
* Restrictions in the form of:
* ... AND column2 IN (1, 2, 3)
* For non-filtering cases (when the preceeding clustering column and a partition key are
* restricted), are handled in {@link #getColumnFilter(CFMetaData, QueryOptions, SuperColumnRestrictions)} by
* adding multiple collection paths to the {@link ColumnFilter}
*/
private final SingleColumnRestriction.SuperColumnKeyINRestriction keyINRestriction;
/**
* Restrictions in the form of:
* ... AND column2 = 1
* For non-filtering cases (when the preceeding clustering column and a partition key are
* restricted), will be handled by converting the restriction to the column filter on
* the collection key in {@link #getColumnFilter(CFMetaData, QueryOptions, SuperColumnRestrictions)}
*/
private final SingleColumnRestriction.SuperColumnKeyEQRestriction keyEQRestriction;
public SuperColumnRestrictions(Iterator restrictions)
{
// In order to keep the fields final, assignments have to be done outside the loop
SingleColumnRestriction.SuperColumnMultiSliceRestriction multiSliceRestriction = null;
SingleColumnRestriction.SuperColumnKeySliceRestriction keySliceRestriction = null;
SingleColumnRestriction.SuperColumnKeyINRestriction keyINRestriction = null;
SingleColumnRestriction.SuperColumnMultiEQRestriction multiEQRestriction = null;
SingleColumnRestriction.SuperColumnKeyEQRestriction keyEQRestriction = null;
while (restrictions.hasNext())
{
SingleRestriction restriction = restrictions.next();
if (restriction instanceof SingleColumnRestriction.SuperColumnMultiSliceRestriction)
multiSliceRestriction = (SingleColumnRestriction.SuperColumnMultiSliceRestriction) restriction;
else if (restriction instanceof SingleColumnRestriction.SuperColumnKeySliceRestriction)
keySliceRestriction = (SingleColumnRestriction.SuperColumnKeySliceRestriction) restriction;
else if (restriction instanceof SingleColumnRestriction.SuperColumnKeyINRestriction)
keyINRestriction = (SingleColumnRestriction.SuperColumnKeyINRestriction) restriction;
else if (restriction instanceof SingleColumnRestriction.SuperColumnMultiEQRestriction)
multiEQRestriction = (SingleColumnRestriction.SuperColumnMultiEQRestriction) restriction;
else if (restriction instanceof SingleColumnRestriction.SuperColumnKeyEQRestriction)
keyEQRestriction = (SingleColumnRestriction.SuperColumnKeyEQRestriction) restriction;
}
this.multiSliceRestriction = multiSliceRestriction;
this.keySliceRestriction = keySliceRestriction;
this.keyINRestriction = keyINRestriction;
this.multiEQRestriction = multiEQRestriction;
this.keyEQRestriction = keyEQRestriction;
}
}
}
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