NoSQLHandle¶
- class borneo.NoSQLHandle(config)[source]¶
Bases:
object
NoSQLHandle is a handle that can be used to access Oracle NoSQL tables. To create a connection represented by NoSQLHandle, request an instance using
NoSQLHandleConfig
, which allows an application to specify default values and other configuration information to be used by the handle.The same interface is available to both users of the Oracle NoSQL Database Cloud Service and the on-premise Oracle NoSQL Database; however, some methods and/or parameters are specific to each environment. The documentation has notes about whether a class, method, or parameter is environment-specific. Unless otherwise noted they are applicable to both environments.
A handle has memory and network resources associated with it. Consequently, the
close()
method must be invoked to free up the resources when the application is done using the handle. To minimize network activity as well as resource allocation and deallocation overheads, it’s best to avoid repeated creation and closing of handles. For example, creating and closing a handle around each operation, would incur large resource allocation overheads resulting in poor application performance.A handle permits concurrent operations, so a single handle is sufficient to access tables in a multi-threaded application. The creation of multiple handles incurs additional resource overheads without providing any performance benefit.
With the exception of
close()
the operations on this interface follow a similar pattern. They accept a Request object containing parameters, both required and optional. They return a Result object containing results. Operation failures throw exceptions. Unique subclasses of Request and Result exist for most operations, containing information specific to the operation. All of these operations result in remote calls across a network.All Request instances support specification of parameters for the operation as well as the ability to override default parameters which may have been specified in
NoSQLHandleConfig
, such as request timeouts, etc.Objects returned by methods of this interface can only be used safely by one thread at a time unless synchronized externally. Request objects are not copied and must not be modified by the application while a method on this interface is using them.
For Error and Exception Handling, on success all methods in this interface return Result objects. Errors are thrown as exceptions. Exceptions that may be retried may succeed on retry. These are instances of
RetryableException
. Exceptions that may not be retried and if retried, will fail again. Exceptions that may be retried return True forRetryableException.ok_to_retry()
while those that may not will return False. Examples of retryable exceptions are those which indicate resource consumption violations such asOperationThrottlingException
. Examples of exceptions that should not be retried areIllegalArgumentException
,TableNotFoundException
, and any other exception indicating a syntactic or semantic error.Instances of NoSQLHandle are thread-safe and expected to be shared among threads.
- Parameters:
config (NoSQLHandleConfig) – an instance of NoSQLHandleConfig.
- Raises:
IllegalArgumentException – raises the exception if config is not an instance of NoSQLHandleConfig.
Methods Summary
close
()Close the NoSQLHandle.
delete
(request)Deletes a row from a table.
do_system_request
(statement[, timeout_ms, ...])On-premise only.
do_table_request
(request, timeout_ms, ...)A convenience method that performs a TableRequest and waits for completion of the operation.
get
(request)Gets the row associated with a primary key.
get_indexes
(request)Returns information about and index, or indexes on a table.
get_table
(request)Gets static information about the specified table including its state, provisioned throughput and capacity and schema.
get_table_usage
(request)Cloud service only.
On-premise only.
On-premise only.
list_tables
(request)Lists tables, returning table names.
On-premise only.
multi_delete
(request)Deletes multiple rows from a table in an atomic operation.
prepare
(request)Prepares a query for execution and reuse.
put
(request)Puts a row into a table.
query
(request)Queries a table based on the query statement specified in the
QueryRequest
.query_iterable
(request)Queries a table based on the query statement specified in the
QueryRequest
.system_request
(request)On-premise only.
system_status
(request)On-premise only.
table_request
(request)Performs an operation on a table.
write_multiple
(request)Executes a sequence of operations associated with a table that share the same shard key portion of their primary keys, all the specified operations are executed within the scope of a single transaction.
Methods Documentation
- delete(request)[source]¶
Deletes a row from a table. The row is identified using a primary key value supplied in
DeleteRequest.set_key()
.By default a delete operation is unconditional and will succeed if the specified row exists. Delete operations can be made conditional based on whether the
Version
of an existing row matches that supplied byDeleteRequest.set_match_version()
.It is also possible, on failure, to return information about the existing row. The row, including it’s
Version
can be optionally returned if a delete operation fails because of a Version mismatch. The existing row information will only be returned ifDeleteRequest.set_return_row()
is True and the operation fails becauseDeleteRequest.set_match_version()
is used and the operation fails because the row exists and its version does not match. Use ofDeleteRequest.set_return_row()
may result in additional consumed read capacity. If the operation is successful there will be no information returned about the previous row.- Parameters:
request (DeleteRequest) – the input parameters for the operation.
- Returns:
the result of the operation.
- Return type:
- Raises:
IllegalArgumentException – raises the exception if request is not an instance of
DeleteRequest
.NoSQLException – raises the exception if the operation cannot be performed for any other reason.
- do_system_request(statement, timeout_ms=30000, poll_interval_ms=1000)[source]¶
On-premise only.
A convenience method that performs a SystemRequest and waits for completion of the operation. This is the same as calling
system_request()
then callingSystemResult.wait_for_completion()
. If the operation fails an exception is thrown.System requests are those related to namespaces and security and are generally independent of specific tables. Examples of statements include
CREATE NAMESPACE mynamespace
CREATE USER some_user IDENTIFIED BY password
CREATE ROLE some_role
GRANT ROLE some_role TO USER some_user
- Parameters:
statement (str) – the system statement for the operation.
timeout_ms (int) – the amount of time to wait for completion, in milliseconds.
poll_interval_ms (int) – the polling interval for the wait operation.
- Returns:
the result of the system request.
- Return type:
- Raises:
IllegalArgumentException – raises the exception if any of the parameters are invalid or required parameters are missing.
RequestTimeoutException – raises the exception if the operation times out.
NoSQLException – raises the exception if the operation cannot be performed for any other reason.
- do_table_request(request, timeout_ms, poll_interval_ms)[source]¶
A convenience method that performs a TableRequest and waits for completion of the operation. This is the same as calling
table_request()
then callingTableResult.wait_for_completion()
. If the operation fails an exception is thrown. All parameters are required.- Parameters:
request (TableRequest) – the
TableRequest
to perform.timeout_ms (int) – the amount of time to wait for completion, in milliseconds.
poll_interval_ms (int) – the polling interval for the wait operation.
- Returns:
the result of the table request.
- Return type:
- Raises:
IllegalArgumentException – raises the exception if any of the parameters are invalid or required parameters are missing.
RequestTimeoutException – raises the exception if the operation times out.
NoSQLException – raises the exception if the operation cannot be performed for any other reason.
- get(request)[source]¶
Gets the row associated with a primary key. On success the value of the row is available using the
GetResult.get_value()
operation. If there are no matching rows that method will return None.The default consistency used for the operation is Consistency.EVENTUAL unless an explicit value has been set using
NoSQLHandleConfig.set_consistency()
orGetRequest.set_consistency()
. Use of Consistency.ABSOLUTE may affect latency of the operation and may result in additional cost for the operation.- Parameters:
request (GetRequest) – the input parameters for the operation.
- Returns:
the result of the operation.
- Return type:
- Raises:
IllegalArgumentException – raises the exception if request is not an instance of
GetRequest
.NoSQLException – raises the exception if the operation cannot be performed for any other reason.
- get_indexes(request)[source]¶
Returns information about and index, or indexes on a table. If no index name is specified in the
GetIndexesRequest
, then information on all indexes is returned.- Parameters:
request (GetIndexesRequest) – the input parameters for the operation.
- Returns:
the result of the operation.
- Return type:
- Raises:
IllegalArgumentException – raises the exception if request is not an instance of
GetIndexesRequest
.NoSQLException – raises the exception if the operation cannot be performed for any other reason.
- get_table(request)[source]¶
Gets static information about the specified table including its state, provisioned throughput and capacity and schema. Dynamic information such as usage is obtained using
get_table_usage()
. Throughput, capacity and usage information is only available when using the Cloud Service and will be None or not defined on-premise.- Parameters:
request (GetTableRequest) – the input parameters for the operation.
- Returns:
the result of the operation.
- Return type:
- Raises:
IllegalArgumentException – raises the exception if request is not an instance of
GetTableRequest
.TableNotFoundException – raises the exception if the specified table does not exist.
NoSQLException – raises the exception if the operation cannot be performed for any other reason.
- get_table_usage(request)[source]¶
Cloud service only.
Gets dynamic information about the specified table such as the current throughput usage. Usage information is collected in time slices and returned in individual usage records. It is possible to specify a time-based range of usage records using input parameters.
- Parameters:
request (TableUsageRequest) – the input parameters for the operation.
- Returns:
the result of the operation.
- Return type:
- Raises:
IllegalArgumentException – raises the exception if request is not an instance of
TableUsageRequest
.TableNotFoundException – raises the exception if the specified table does not exist.
NoSQLException – raises the exception if the operation cannot be performed for any other reason.
- list_namespaces()[source]¶
On-premise only.
Returns the namespaces in a store as a list of string.
- Returns:
the namespaces, or None if none are found.
- Return type:
list(str)
- list_roles()[source]¶
On-premise only.
Returns the roles in a store as a list of string.
- Returns:
the list of roles, or None if none are found.
- Return type:
list(str)
- list_tables(request)[source]¶
Lists tables, returning table names. If further information about a specific table is desired the
get_table()
interface may be used. If a given identity has access to a large number of tables the list may be paged using input parameters.- Parameters:
request (ListTablesRequest) – the input parameters for the operation.
- Returns:
the result of the operation.
- Return type:
- Raises:
IllegalArgumentException – raises the exception if request is not an instance of
ListTablesRequest
.NoSQLException – raises the exception if the operation cannot be performed for any other reason.
- list_users()[source]¶
On-premise only.
Returns the users in a store as a list of
UserInfo
.- Returns:
the list of users, or None if none are found.
- Return type:
list(UserInfo)
- multi_delete(request)[source]¶
Deletes multiple rows from a table in an atomic operation. The key used may be partial but must contain all of the fields that are in the shard key. A range may be specified to delete a range of keys.
- Parameters:
request (MultiDeleteRequest) – the input parameters for the operation.
- Returns:
the result of the operation.
- Return type:
- Raises:
IllegalArgumentException – raises the exception if request is not an instance of
MultiDeleteRequest
.NoSQLException – raises the exception if the operation cannot be performed for any other reason.
- prepare(request)[source]¶
Prepares a query for execution and reuse. See
query()
for general information and restrictions. It is recommended that prepared queries are used when the same query will run multiple times as execution is much more efficient than starting with a query string every time. The query language and API support query variables to assist with re-use.- Parameters:
request (PrepareRequest) – the input parameters for the operation.
- Returns:
the result of the operation.
- Return type:
- Raises:
IllegalArgumentException – raises the exception if request is not an instance of
PrepareRequest
.NoSQLException – raises the exception if the operation cannot be performed for any other reason.
- put(request)[source]¶
Puts a row into a table. This method creates a new row or overwrites an existing row entirely. The value used for the put is in the
PutRequest
object and must contain a complete primary key and all required fields.It is not possible to put part of a row. Any fields that are not provided will be defaulted, overwriting any existing value. Fields that are not noneable or defaulted must be provided or an exception will be thrown.
By default a put operation is unconditional, but put operations can be conditional based on existence, or not, of a previous value as well as conditional on the
Version
of the existing value.Use PutOption.IF_ABSENT to do a put only if there is no existing row that matches the primary key.
Use PutOption.IF_PRESENT to do a put only if there is an existing row that matches the primary key.
Use PutOption.IF_VERSION to do a put only if there is an existing row that matches the primary key and its
Version
matches that provided.It is also possible, on failure, to return information about the existing row. The row, including it’s
Version
can be optionally returned if a put operation fails because of a Version mismatch or if the operation fails because the row already exists. The existing row information will only be returned ifPutRequest.set_return_row()
is True and one of the following occurs:The PutOption.IF_ABSENT is used and the operation fails because the row already exists.
The PutOption.IF_VERSION is used and the operation fails because the row exists and its version does not match.
Use of
PutRequest.set_return_row()
may result in additional consumed read capacity. If the operation is successful there will be no information returned about the previous row.- Parameters:
request (PutRequest) – the input parameters for the operation.
- Returns:
the result of the operation.
- Return type:
- Raises:
IllegalArgumentException – raises the exception if request is not an instance of
PutRequest
.NoSQLException – raises the exception if the operation cannot be performed for any other reason.
- query(request)[source]¶
Queries a table based on the query statement specified in the
QueryRequest
.Queries that include a full shard key will execute much more efficiently than more distributed queries that must go to multiple shards.
Table and system-style queries such as “CREATE TABLE …” or “DROP TABLE …” are not supported by these interfaces. Those operations must be performed using
table_request()
orsystem_request()
as appropriate.The amount of data read by a single query request is limited by a system default and can be further limited using
QueryRequest.set_max_read_kb()
. This limits the amount of data read and not the amount of data returned, which means that a query can return zero results but still have more data to read. This situation is detected by checking if theQueryRequest
is done usingQueryRequest.is_done()
. For this reason queries should always operate in a loop, acquiring more results, untilQueryRequest.is_done()
returns True, indicating that the query is done.- Parameters:
request (QueryRequest) – the input parameters for the operation.
- Returns:
the result of the operation.
- Return type:
- Raises:
IllegalArgumentException – raises the exception if request is not an instance of
QueryRequest
.NoSQLException – raises the exception if the operation cannot be performed for any other reason.
- query_iterable(request: QueryRequest) QueryIterableResult [source]¶
Queries a table based on the query statement specified in the
QueryRequest
.Queries that include a full shard key will execute much more efficiently than more distributed queries that must go to multiple shards.
Table and system-style queries such as “CREATE TABLE …” or “DROP TABLE …” are not supported by these interfaces. Those operations must be performed using
table_request()
orsystem_request()
as appropriate.The amount of data read by a single query request is limited by a system default and can be further limited using
QueryRequest.set_max_read_kb()
. This limits the amount of data read and not the amount of data returned.- Parameters:
request (QueryRequest) – the input parameters for the operation.
- Returns:
the result of the operation.
- Return type:
- Raises:
IllegalArgumentException – raises the exception if request is not an instance of
QueryRequest
.NoSQLException – raises the exception if the operation cannot be performed for any other reason.
- Versionadded:
5.3.6
- system_request(request)[source]¶
On-premise only.
Performs a system operation on the system, such as administrative operations that don’t affect a specific table. For table-specific operations use
table_request()
ordo_table_request()
.Examples of statements in the
SystemRequest
passed to this method include:CREATE NAMESPACE mynamespace
CREATE USER some_user IDENTIFIED BY password
CREATE ROLE some_role
GRANT ROLE some_role TO USER some_user
This operation is implicitly asynchronous. The caller must poll using methods on
SystemResult
to determine when it has completed.- Parameters:
request (SystemRequest) – the input parameters for the operation.
- Returns:
the result of the operation.
- Return type:
- Raises:
IllegalArgumentException – raises the exception if request is not an instance of
SystemRequest
.NoSQLException – raises the exception if the operation cannot be performed for any other reason.
- system_status(request)[source]¶
On-premise only.
Checks the status of an operation previously performed using
system_request()
.- Parameters:
request (SystemStatusRequest) – the input parameters for the operation.
- Returns:
the result of the operation.
- Return type:
- Raises:
IllegalArgumentException – raises the exception if request is not an instance of
SystemStatusRequest
.NoSQLException – raises the exception if the operation cannot be performed for any other reason.
- table_request(request)[source]¶
Performs an operation on a table. This method is used for creating and dropping tables and indexes as well as altering tables. Only one operation is allowed on a table at any one time.
This operation is implicitly asynchronous. The caller must poll using methods on
TableResult
to determine when it has completed.- Parameters:
request (TableRequest) – the input parameters for the operation.
- Returns:
the result of the operation.
- Return type:
- Raises:
IllegalArgumentException – raises the exception if request is not an instance of
TableRequest
.NoSQLException – raises the exception if the operation cannot be performed for any other reason.
- write_multiple(request)[source]¶
Executes a sequence of operations associated with a table that share the same shard key portion of their primary keys, all the specified operations are executed within the scope of a single transaction.
There are some size-based limitations on this operation:
The max number of individual operations (put, delete) in a single WriteMultipleRequest is 50.
The total request size is limited to 25MB.
- Parameters:
request (WriteMultipleRequest) – the input parameters for the operation.
- Returns:
the result of the operation.
- Return type:
- Raises:
IllegalArgumentException – raises the exception if request is not an instance of
WriteMultipleRequest
.RowSizeLimitException – raises the exception if data size in an operation exceeds the limit.
BatchOperationNumberLimitException – raises the exception if the number of operations exceeds this limit.
NoSQLException – raises the exception if the operation cannot be performed for any other reason.