public final class KeyRange extends Object implements Serializable
A range has a start key and an end key. These keys can be open or closed, indicating if the range includes rows with that key.
For example, consider the following table definition:
CREATE TABLE UserEvents ( UserName STRING(MAX), EventDate STRING(10), ) PRIMARY KEY(UserName, EventDate);The following keys name rows in this table:
Key.of("Bob", "2014-09-23")
Key.of("Alfred", "2015-06-12")
UserEvents
table's PRIMARY KEY
clause names two columns, each UserEvents
key has two elements; the first is the UserName
, and the second is the EventDate
.
Key ranges with multiple components are interpreted lexicographically by component using the table or index key's declared sort order. For example, the following range returns all events for user "Bob" that occurred in the year 2015:
KeyRange.closedClosed( Key.of("Bob", "2015-01-01"), Key.of("Bob", "2015-12-31"))Start and end keys can omit trailing key components. This affects the inclusion and exclusion of rows that exactly match the provided key components: if the key is closed, then rows that exactly match the provided components are included; if the key is open, then rows that exactly match are not included.
For example, the following range includes all events for "Bob" that occurred during and after the year 2000:
KeyRange.closedClosed( Key.of("Bob", "2000-01-01"), Key.of("Bob"))The next example retrieves all events for "Bob":
KeyRange.prefix(Key.of("Bob"))To retrieve events before the year 2000:
KeyRange.closedOpen( Key.of("Bob"), Key.of("Bob", "2000-01-01"))The following range includes all rows in the table:
KeyRange.all()This range returns all users whose
UserName
begins with any character from A to C:
KeyRange.closedOpen(Key.of("A"), Key.of("D"))This range returns all users whose
UserName
begins with B:
KeyRange.closedOpen(Key.of("B"), Key.of("C"))Key ranges honor column sort order. For example, suppose a table is defined as follows:
CREATE TABLE DescendingSortedTable { Key INT64, ... ) PRIMARY KEY(Key DESC);The following range retrieves all rows with key values between 1 and 100 inclusive:
KeyRange.closedClosed(Key.of(100), Key.of(1))Note that 100 is passed as the start, and 1 is passed as the end, because
Key
is a
descending column in the schema.
KeyRange
instances are immutable.
Modifier and Type | Class and Description |
---|---|
static class |
KeyRange.Builder
Builder for
KeyRange instances. |
static class |
KeyRange.Endpoint
Defines whether a range includes or excludes its endpoint keys.
|
Modifier and Type | Method and Description |
---|---|
static KeyRange |
closedClosed(Key start,
Key end)
Returns a key range from
start inclusive to end inclusive. |
static KeyRange |
closedOpen(Key start,
Key end)
Returns a key range from
start inclusive to end exclusive. |
boolean |
equals(Object o) |
KeyRange.Endpoint |
geEndType()
Indicates whether the end key is inclusive (
CLOSED ) or exclusive (OPEN ). |
Key |
getEnd()
Returns the end key of the range.
|
Key |
getStart()
Returns the start key of the range.
|
KeyRange.Endpoint |
getStartType()
Indicates whether the start key is inclusive (
CLOSED ) or exclusive (OPEN ). |
int |
hashCode() |
static KeyRange.Builder |
newBuilder()
Returns a new builder for constructing a range.
|
static KeyRange |
openClosed(Key start,
Key end)
Returns a key range from
start exclusive to end inclusive. |
static KeyRange |
openOpen(Key start,
Key end)
Returns a key range from
start exclusive to end exclusive. |
static KeyRange |
prefix(Key prefix)
Returns a key range that covers all keys where the first
prefix.size() components match
prefix exactly. |
KeyRange.Builder |
toBuilder()
Returns a builder initialized with the value of this range.
|
String |
toString() |
public static KeyRange closedOpen(Key start, Key end)
start
inclusive to end
exclusive.public static KeyRange closedClosed(Key start, Key end)
start
inclusive to end
inclusive.public static KeyRange openOpen(Key start, Key end)
start
exclusive to end
exclusive.public static KeyRange openClosed(Key start, Key end)
start
exclusive to end
inclusive.public static KeyRange prefix(Key prefix)
prefix.size()
components match
prefix
exactly.public static KeyRange.Builder newBuilder()
public Key getStart()
public KeyRange.Endpoint getStartType()
CLOSED
) or exclusive (OPEN
).public Key getEnd()
public KeyRange.Endpoint geEndType()
CLOSED
) or exclusive (OPEN
).public KeyRange.Builder toBuilder()
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