Constructor
Represents cluster and schema information.
The metadata class acts as a internal state of the driver.
Parameters:
| Name |
Type |
Description |
options |
ClientOptions
|
|
controlConnection |
ControlConnection
|
Control connection used to retrieve information. |
Methods
clearPrepared()
Clears the internal state related to the prepared statements.
Following calls to the Client using the prepare flag will re-prepare the statements.
getAggregate(keyspaceName, name, signature, callback)
Gets a definition of CQL aggregate for a given name and signature.
When trying to retrieve the same aggregate definition concurrently,
it will query once and invoke all callbacks with the retrieved information.
Parameters:
| Name |
Type |
Description |
keyspaceName |
String
|
Name of the keyspace |
name |
String
|
Name of the aggregate |
signature |
Array.<String>
|
Array.<{code, info}>
|
Array of types of the parameters. |
callback |
function
|
The callback with the err as a first parameter and the Aggregate as second parameter. |
getAggregates(keyspaceName, name, callback)
Gets the definition of CQL aggregate for a given name.
When trying to retrieve the same aggregates definition concurrently,
it will query once and invoke all callbacks with the retrieved information.
Parameters:
| Name |
Type |
Description |
keyspaceName |
String
|
Name of the keyspace |
name |
String
|
Name of the Function |
callback |
function
|
The callback with the err as a first parameter and the array of Aggregate as second parameter. |
getFunction(keyspaceName, name, signature, callback)
Gets a definition of CQL function for a given name and signature.
When trying to retrieve the same function definition concurrently,
it will query once and invoke all callbacks with the retrieved information.
Parameters:
| Name |
Type |
Description |
keyspaceName |
String
|
Name of the keyspace |
name |
String
|
Name of the Function |
signature |
Array.<String>
|
Array.<{code, info}>
|
Array of types of the parameters. |
callback |
function
|
The callback with the err as a first parameter and the SchemaFunction as second parameter. |
getFunctions(keyspaceName, name, callback)
Gets the definition of CQL functions for a given name.
When trying to retrieve the same function definition concurrently,
it will query once and invoke all callbacks with the retrieved information.
Parameters:
| Name |
Type |
Description |
keyspaceName |
String
|
Name of the keyspace |
name |
String
|
Name of the Function |
callback |
function
|
The callback with the err as a first parameter and the array of SchemaFunction as second parameter. |
getMaterializedView(keyspaceName, name, callback)
Gets the definition of a CQL materialized view for a given name.
Note that, unlike the rest of the Metadata methods, this method does not cache the result for following
calls, as the current version of the Cassandra native protocol does not support schema change events for
materialized views. Each call to this method will produce one or more queries to the cluster.
Parameters:
| Name |
Type |
Description |
keyspaceName |
String
|
Name of the keyspace |
name |
String
|
Name of the materialized view |
callback |
function
|
The callback with the err as a first parameter and the MaterializedView as second parameter. |
getReplicas(keyspaceName, tokenBuffer) → {Array}
Gets the host list representing the replicas that contain such partition.
Parameters:
| Name |
Type |
Description |
keyspaceName |
String
|
|
tokenBuffer |
Buffer
|
|
Returns:
-
Type
-
Array
getTable(keyspaceName, name, callback)
Gets the definition of a table.
When trying to retrieve the same table definition concurrently,
it will query once and invoke all callbacks with the retrieved information.
Parameters:
| Name |
Type |
Description |
keyspaceName |
String
|
Name of the keyspace |
name |
String
|
Name of the Table |
callback |
function
|
The callback with the err as a first parameter and the TableMetadata as second parameter. |
getTrace(traceId, callback)
Gets the trace session generated by Cassandra when query tracing is enabled for the
query. The trace itself is stored in Cassandra in the sessions and
events table in the system_traces keyspace and can be
retrieve manually using the trace identifier.
Parameters:
| Name |
Type |
Description |
traceId |
Uuid
|
Identifier of the trace session. |
callback |
function
|
The callback with the err as first parameter and the query trace as second parameter |
getUdt(keyspaceName, name, callback)
Gets the definition of an user defined type.
When trying to retrieve the same udt definition concurrently,
it will query once and invoke all callbacks with the retrieved information.
Parameters:
| Name |
Type |
Description |
keyspaceName |
String
|
Name of the keyspace |
name |
String
|
Name of the UDT |
callback |
function
|
|
refreshKeyspace(name, callbackopt)
Gets the keyspace metadata information and updates the internal state of the driver.
Parameters:
| Name |
Type |
Attributes |
Description |
name |
String
|
|
Name of the keyspace. |
callback |
function
|
<optional>
|
Optional callback. |
refreshKeyspaces(callbackopt)
Gets the metadata information of all the keyspaces and updates the internal state of the driver.
Parameters:
| Name |
Type |
Attributes |
Description |
callback |
function
|
<optional>
|
Optional callback. |