IDBIndex Interface
The IDBIndex
interface of the IndexedDB API provides asynchronous access to an index in a database. An index is a kind of object store for looking up records in another object store, called the referenced object store. You use this interface to retrieve data.
Inherits from: EventTarget
Methods
Code IDBRequest count([key_OR_range]) #
Returns an IDBRequest object, and in a separate thread, returns the number of records within a key range. For example, if you want to see how many records are between keys 1000 and 2000 in an object store, you can write the following: var req = store.count(IDBKeyRange.bound(1000, 2000));
IDBRequest count ( in optional any key ) raises (IDBDatabaseException);
Parameters
- key
- The key or key range that identifies the record to be counted.
Exceptions
This method can raise a IDBDatabaseException with the following code:
Attribute | Description |
---|---|
DATA_ERR | The key parameter was not a valid value. |
NOT_ALLOWED_ERR | The request was made on a source object that has been deleted or removed. |
IDBRequest count([key_OR_range]);
Code IDBRequest get(key) #
Returns an IDBRequest object, and, in a separate thread, finds either:
- The value in the referenced object store that corresponds to the given key.
- The first corresponding value, if
key
is a key range.
If a value is successfully found, then a structured clone of it is created and set as the result
of the request object.
IDBRequest get ( in any key ) raises (IDBDatabaseException);
Parameters
- key
- The key or key range that identifies the record to be retrieved.
Exceptions
This method can raise an IDBDatabaseException with the following code:
Attribute | Description |
---|---|
TRANSACTION_INACTIVE_ERR | The index's transaction is not active. |
DATA_ERR | The key parameter was not a valid value. |
NOT_ALLOWED_ERR | The request was made on a source object that has been deleted or removed. |
IDBRequest get(key);
Code IDBRequest getKey(key) #
Returns an IDBRequest object, and, in a separate thread, finds either:
- The value in the index that corresponds to the given key
- The first corresponding value, if
key
is a key range.
If a value is successfully found, then a structured clone of it is created and set as the result
of the request object.
IDBRequest getKey ( in any key ) raises (IDBDatabaseException);
Parameters
- key
- The key or key range that identifies the record to be retrieved.
Exceptions
This method can raise a IDBDatabaseException with the following code:
Attribute | Description |
---|---|
TRANSACTION_INACTIVE_ERR | The index's transaction is not active. |
DATA_ERR | The key parameter was not a valid value. |
NOT_ALLOWED_ERR | The request was made on a source object that has been deleted or removed. |
IDBRequest getKey(key);
Code IDBRequest openCursor([key_OR_range, direction]) #
Returns an IDBRequest object, and, in a separate thread, creates a cursor over the specified key range. The method sets the position of the cursor to the appropriate record, based on the specified direction.
- If the key range is not specified or is null, then the range includes all the records.
- If at least one record matches the key range, then a success event is fired on the result object, with its result set to the new IDBCursor object; the
value
of the cursor object is set to a structured clone of the referenced value. - If no records match the key range, then then an error event is fired on the request object, with its
code
set toNOT_FOUND_ERR
and a suitablemessage
.
IDBRequest openCursor ( in optional any? range, in optional unsigned short direction ) raises (IDBDatabaseException);
Parameters
- range
- Optional. The key range to use as the cursor's range.
- direction
- Optional. The cursor's required direction. See IDBCursor Constants for possible values.
Exceptions
This method can raise an IDBDatabaseException with the following code:
Attribute | Description |
---|---|
TRANSACTION_INACTIVE_ERR | The index's transaction is not active. |
DATA_ERR | The key parameter was not a valid value. |
NOT_ALLOWED_ERR | The request was made on a source object that has been deleted or removed. |
IDBRequest openCursor([key_OR_range, direction]);
Code IDBRequest openKeyCursor([key_OR_range, direction]) #
Returns an IDBRequest object, and, in a separate thread, creates a cursor over the specified key range, as arranged by this index. The method sets the position of the cursor to the appropriate record, based on the specified direction.
- If the key range is not specified or is null, then the range includes all the records.
- If at least one record matches the key range, then a success event is fired on the result object, with its result set to the new IDBCursor object; the
value
of the cursor object is set to the value of the found record. - If no records match the key range, then then an error event is fired on the request object, with its
code
set toNOT_FOUND_ERR
and a suitablemessage
.
IDBRequest openKeyCursor ( in optional any? range, in optional unsigned short direction ) raises (IDBDatabaseException);
Parameters
- range
- Optional. The key range to use as the cursor's range.
- direction
- Optional. The cursor's required direction. See IDBCursor Constants for possible values.
Exceptions
This method can raise an IDBDatabaseException with the following code:
Attribute | Description |
---|---|
TRANSACTION_INACTIVE_ERR | The index's transaction is not active. |
DATA_ERR | The key parameter was not a valid value. |
NOT_ALLOWED_ERR | The request was made on a source object that has been deleted or removed. |
IDBRequest openKeyCursor([key_OR_range, direction]);
Fields
Code final keyPath #
final Dynamic keyPath;
Code final IDBObjectStore objectStore #
final IDBObjectStore objectStore;
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