Package com.google.cloud.spanner
Class KeyRange
java.lang.Object
com.google.cloud.spanner.KeyRange
- All Implemented Interfaces:
Serializable
Represents a range of rows in a table or index.
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.
- See Also:
-
Nested Class Summary
Modifier and TypeClassDescriptionstatic class
Builder forKeyRange
instances.static enum
Defines whether a range includes or excludes its endpoint keys. -
Method Summary
Modifier and TypeMethodDescriptionstatic KeyRange
closedClosed
(Key start, Key end) Returns a key range fromstart
inclusive toend
inclusive.static KeyRange
closedOpen
(Key start, Key end) Returns a key range fromstart
inclusive toend
exclusive.boolean
Indicates whether the end key is inclusive (CLOSED
) or exclusive (OPEN
).getEnd()
Returns the end key of the range.getStart()
Returns the start key of the range.Indicates whether the start key is inclusive (CLOSED
) or exclusive (OPEN
).int
hashCode()
static KeyRange.Builder
Returns a new builder for constructing a range.static KeyRange
openClosed
(Key start, Key end) Returns a key range fromstart
exclusive toend
inclusive.static KeyRange
Returns a key range fromstart
exclusive toend
exclusive.static KeyRange
Returns a key range that covers all keys where the firstprefix.size()
components matchprefix
exactly.Returns a builder initialized with the value of this range.toString()
-
Method Details
-
closedOpen
Returns a key range fromstart
inclusive toend
exclusive. -
closedClosed
Returns a key range fromstart
inclusive toend
inclusive. -
openOpen
Returns a key range fromstart
exclusive toend
exclusive. -
openClosed
Returns a key range fromstart
exclusive toend
inclusive. -
prefix
Returns a key range that covers all keys where the firstprefix.size()
components matchprefix
exactly. -
newBuilder
Returns a new builder for constructing a range. -
getStart
Returns the start key of the range. -
getStartType
Indicates whether the start key is inclusive (CLOSED
) or exclusive (OPEN
). -
getEnd
Returns the end key of the range. -
geEndType
Indicates whether the end key is inclusive (CLOSED
) or exclusive (OPEN
). -
toBuilder
Returns a builder initialized with the value of this range. -
toString
-
equals
-
hashCode
public int hashCode()
-