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package org.hsqldb.index;

import org.hsqldb.RangeVariable.RangeVariableConditions;
import org.hsqldb.Row;
import org.hsqldb.SchemaObject;
import org.hsqldb.Session;
import org.hsqldb.TableBase;
import org.hsqldb.navigator.RowIterator;
import org.hsqldb.persist.PersistentStore;
import org.hsqldb.types.Type;

Author:
Fred Toussi (fredt@users dot sourceforge.net)
Version:
2.5.0
Since:
1.9.0/**
 *
 * @author Fred Toussi (fredt@users dot sourceforge.net)
 * @version 2.5.0
 * @since 1.9.0
 */
public interface Index extends SchemaObject {

    int INDEX_NONE       = 0;
    int INDEX_NON_UNIQUE = 1;
    int INDEX_UNIQUE     = 2;

    //
    double minimumSelectivity = 16;
    double cachedFactor       = 8;
    int    probeDepth         = 4;

    //
    Index[]    emptyArray    = new Index[]{};
    IndexUse[] emptyUseArray = new IndexUse[]{};

    IndexUse[] asArray();

    RowIterator emptyIterator();

    int getPosition();

    void setPosition(int position);

    long getPersistenceId();

    
Returns the count of visible columns used
/**
     * Returns the count of visible columns used
     */
    int getColumnCount();

    
Is this a PRIMARY_KEY index?
/**
     * Is this a PRIMARY_KEY index?
     */
    boolean isPrimaryKey();

    
Is this a UNIQUE index?
/**
     * Is this a UNIQUE index?
     */
    boolean isUnique();

    
Does this index belong to a constraint?
/**
     * Does this index belong to a constraint?
     */
    boolean isConstraint();

    
Returns the array containing column indexes for index
/**
     * Returns the array containing column indexes for index
     */
    int[] getColumns();

    
Returns the array containing column indexes for index
/**
     * Returns the array containing column indexes for index
     */
    Type[] getColumnTypes();

    
Returns the count of visible columns used
/**
     * Returns the count of visible columns used
     */
    boolean[] getColumnDesc();

    
Returns the array containing 0, 1, .. column indexes
/**
     * Returns the array containing 0, 1, .. column indexes
     */
    int[] getDefaultColumnMap();

    
Returns a value indicating the order of different types of index in
the list of indexes for a table. The position of the groups of Indexes
in the list in ascending order is as follows:
primary key index
unique constraint indexes
autogenerated foreign key indexes for FK's that reference this table or
 tables created before this table
user created indexes (CREATE INDEX)
autogenerated foreign key indexes for FK's that reference tables created
 after this table
Among a group of indexes, the order is based on the order of creation
of the index.
Returns:
ordinal value/**
     * Returns a value indicating the order of different types of index in
     * the list of indexes for a table. The position of the groups of Indexes
     * in the list in ascending order is as follows:
     *
     * primary key index
     * unique constraint indexes
     * autogenerated foreign key indexes for FK's that reference this table or
     *  tables created before this table
     * user created indexes (CREATE INDEX)
     * autogenerated foreign key indexes for FK's that reference tables created
     *  after this table
     *
     * Among a group of indexes, the order is based on the order of creation
     * of the index.
     *
     * @return ordinal value
     */
    int getIndexOrderValue();

    boolean isForward();

    void setTable(TableBase table);

    TableBase getTable();

    void setClustered(boolean clustered);

    boolean isClustered();

    
Returns the node count.
/**
     * Returns the node count.
     */
    long size(Session session, PersistentStore store);

    long sizeUnique(PersistentStore store);

    double[] searchCost(Session session, PersistentStore store);

    long getNodeCount(Session session, PersistentStore store);

    boolean isEmpty(PersistentStore store);

    int checkIndex(Session session, PersistentStore store);

    
Insert a node into the index
/**
     * Insert a node into the index
     */
    void insert(Session session, PersistentStore store, Row row
                );

    void delete(Session session, PersistentStore store, Row row);

    boolean existsParent(Session session, PersistentStore store,
                         Object[] rowdata, int[] rowColMap);

    
Return the first node equal to the indexdata object. The rowdata has
the same column mapping as this index.
Params:
session – session object
store – store object
matchCount – count of columns to match
Returns:
iterator/**
     * Return the first node equal to the indexdata object. The rowdata has
     * the same column mapping as this index.
     *
     * @param session session object
     * @param store store object
     * @param matchCount count of columns to match
     * @return iterator
     */
    RowIterator findFirstRow(Session session, PersistentStore store,
                             Object[] rowdata, int matchCount,
                             int distinctCount, int compareType,
                             boolean reversed, boolean[] map);

    
Return the first node equal to the rowdata object.
The rowdata has the same column mapping as this table.
Params:
session – session object
store – store object
rowdata – array containing table row data
Returns:
iterator/**
     * Return the first node equal to the rowdata object.
     * The rowdata has the same column mapping as this table.
     *
     * @param session session object
     * @param store store object
     * @param rowdata array containing table row data
     * @return iterator
     */
    RowIterator findFirstRow(Session session, PersistentStore store,
                             Object[] rowdata);

    
Return the first node equal to the rowdata object.
The rowdata has the column mapping provided in rowColMap.
Params:
session – session object
store – store object
rowdata – array containing table row data
Returns:
iterator/**
     * Return the first node equal to the rowdata object.
     * The rowdata has the column mapping provided in rowColMap.
     *
     * @param session session object
     * @param store store object
     * @param rowdata array containing table row data
     * @return iterator
     */
    RowIterator findFirstRow(Session session, PersistentStore store,
                             Object[] rowdata, int[] rowColMap);

    
Finds the first node where the data is not null.
Returns:
iterator/**
     * Finds the first node where the data is not null.
     *
     * @return iterator
     */
    RowIterator findFirstRowNotNull(Session session, PersistentStore store);

    RowIterator firstRow(PersistentStore store);

    
Returns the row for the first node of the index
Returns:
Iterator for first row/**
     * Returns the row for the first node of the index
     *
     * @return Iterator for first row
     */
    RowIterator firstRow(Session session, PersistentStore store,
                         RangeVariableConditions[] conditions,
                         int distinctCount, boolean[] map);

    
Returns the row for the last node of the index
Returns:
last row/**
     * Returns the row for the last node of the index
     *
     * @return last row
     */
    RowIterator lastRow(Session session, PersistentStore store,
                        int distinctCount, boolean[] map);

    
Compares two table rows based on the columns of this index. The rowColMap
parameter specifies which columns of the other table are to be compared
with the colIndex columns of this index. The rowColMap can cover all
or only some columns of this index.
Params:
a – row from another table
rowColMap – column indexes in the other table
b – a full row in this table
Returns:
comparison result, -1,0,+1/**
     * Compares two table rows based on the columns of this index. The rowColMap
     * parameter specifies which columns of the other table are to be compared
     * with the colIndex columns of this index. The rowColMap can cover all
     * or only some columns of this index.
     *
     * @param a row from another table
     * @param rowColMap column indexes in the other table
     * @param b a full row in this table
     *
     * @return comparison result, -1,0,+1
     */
    int compareRowNonUnique(Session session, Object[] a, Object[] b,
                            int[] rowColMap);

    int compareRowNonUnique(Session session, Object[] a, Object[] b,
                            int[] rowColMap, int fieldCount);

    
As above but use the index column data
/**
     * As above but use the index column data
     */
    int compareRowNonUnique(Session session, Object[] a, Object[] b,
                            int fieldcount);

    int compareRow(Session session, Object[] a, Object[] b);

    class IndexUse {

        public Index index;
        public int   columnCount;

        public IndexUse(Index index, int columnCount) {
            this.index       = index;
            this.columnCount = columnCount;
        }
    }
}