com.apple.foundationdb.record.metadata

Class IndexTypes

java.lang.Object

com.apple.foundationdb.record.metadata.IndexTypes

@API(value=MAINTAINED)
public class IndexTypes
extends Object

The standard index types. The type of an Index is just a string, so that new ones can be defined outside the Record Layer core.

See Also:

IndexMaintainerRegistry

Field Summary

Fields

Modifier and Type	Field and Description
static String	COUNT A count of the number of indexed entries.
static String	COUNT_NOT_NULL A count of the number of non-null values for a field.
static String	COUNT_UPDATES A count of the number of times that any indexed record has been updated.
static String	MAX_EVER Deprecated. use MAX_EVER_LONG for compatibility with existing data or MAX_EVER_TUPLE for more flexibility
static String	MAX_EVER_LONG An index remembering the smallest nonnegative integer ever stored.
static String	MAX_EVER_TUPLE An index remembering the greatest value(s) ever stored.
static String	MAX_EVER_VERSION An index remembering the maximum ever value stored where one column is the record version.
static String	MIN_EVER Deprecated. use MIN_EVER_LONG for compatibility with existing data or MIN_EVER_TUPLE for more flexibility
static String	MIN_EVER_LONG An index remembering the smallest nonnegative integer ever stored.
static String	MIN_EVER_TUPLE An index remembering the least value(s) ever stored.
static String	RANK A ranked set index, allowing efficient rank and select operations.
static String	SUM A total of a long-valued field.
static String	TEXT An index on the tokens in a text field.
static String	TIME_WINDOW_LEADERBOARD An index with sliding time window leaderboards.
static String	VALUE A normal index on field values.
static String	VERSION An index like VALUE, but that allows one of the components to be VersionKeyExpression.

Method Summary

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

VALUE

public static final String VALUE

A normal index on field values. The index is ordered, lexicographically if there is more than one field.

See Also:

Constant Field Values

COUNT

public static final String COUNT

A count of the number of indexed entries. If the index's expression is grouped, a separate count is maintained for each group.

See Also:

Constant Field Values

COUNT_UPDATES

public static final String COUNT_UPDATES

A count of the number of times that any indexed record has been updated. Unlike COUNT, the count does not go down when records are deleted.

See Also:

Constant Field Values

COUNT_NOT_NULL

public static final String COUNT_NOT_NULL

A count of the number of non-null values for a field. If the index's expression has more than one field, the count indicates when none of the fields was null.

See Also:

Constant Field Values

SUM

public static final String SUM

A total of a long-valued field.

See Also:

Constant Field Values

MIN_EVER

@Deprecated
public static final String MIN_EVER

Deprecated. use MIN_EVER_LONG for compatibility with existing data or MIN_EVER_TUPLE for more flexibility

Compatible name for MIN_EVER_LONG.

See Also:

Constant Field Values

MAX_EVER

@Deprecated
public static final String MAX_EVER

Deprecated. use MAX_EVER_LONG for compatibility with existing data or MAX_EVER_TUPLE for more flexibility

Compatible name for MAX_EVER_LONG.

See Also:

Constant Field Values

MIN_EVER_TUPLE

public static final String MIN_EVER_TUPLE

An index remembering the least value(s) ever stored. The order of values is the same as for keys: lexicographic among fields and each field ordered by Tuple.compareTo(com.apple.foundationdb.tuple.Tuple).

See Also:

Constant Field Values

MAX_EVER_TUPLE

public static final String MAX_EVER_TUPLE

An index remembering the greatest value(s) ever stored.

See Also:

Constant Field Values

MIN_EVER_LONG

public static final String MIN_EVER_LONG

An index remembering the smallest nonnegative integer ever stored. Because this index does not work with negative numbers or non-integer fields, consider using MIN_EVER_TUPLE instead.

See Also:

Constant Field Values

MAX_EVER_LONG

public static final String MAX_EVER_LONG

An index remembering the smallest nonnegative integer ever stored. Because this index does not work with negative numbers or non-integer fields, consider using MAX_EVER_TUPLE instead.

See Also:

Constant Field Values

MAX_EVER_VERSION

public static final String MAX_EVER_VERSION

An index remembering the maximum ever value stored where one column is the record version. This can be used to detect if there have been any changes to the record store or to subsections of the record store (if there are grouping columns included in the index definition).

This index is like MAX_EVER_TUPLE except that the expression may contain exactly one aggregated column that contains a VersionKeyExpression with one caveat. If a record is written with an incomplete version-stamp, then the aggregate index entry is guaranteed to be updated to include the value from that record. For example, if there are two columns defined as part of the index, and the first corresponds to an integer field while the second corresponds to the record version, then the value stored by this index may go backwards if, for example, one stores a record where the first field has value 2 and has an incomplete version-stamp and then, in a separate transaction, one stores a record with the first field has value 1 and has an incomplete version-stamp.

See Also:

Constant Field Values

RANK

public static final String RANK

A ranked set index, allowing efficient rank and select operations.

See Also:

Constant Field Values

TIME_WINDOW_LEADERBOARD

public static final String TIME_WINDOW_LEADERBOARD

An index with sliding time window leaderboards.

See Also:

Constant Field Values

VERSION

public static final String VERSION

An index like VALUE, but that allows one of the components to be VersionKeyExpression.

See Also:

Constant Field Values

TEXT

public static final String TEXT

An index on the tokens in a text field.

See Also:

Constant Field Values