View Source FDB.Option (fdb v6.3.23-0)
This module contains all the options that are accepted by various functions. These options are autogenerated from xml file.
Link to this section Summary
Functions
Used to add a read conflict range
Used to add a write conflict range
Hexadecimal ID
Max location cache entries
Hexadecimal ID
Max outstanding watches
Snapshot read operations will not see the results of writes done in the same transaction. This was the default behavior prior to API version 300.
Snapshot read operations will see the results of writes done in the same transaction. This is the default behavior.
Allows get
operations to read from sections of keyspace that have become unreadable because of versionstamp operations. This sets the bypass_unreadable
option of each transaction created by this database. See the transaction option description for more information.
The read version will be committed, and usually will be the latest committed, but might not be the latest committed in the event of a simultaneous fault and misbehaving clock.
Addresses returned by get_addresses_for_key include the port when enabled. As of api version 630, this option is enabled by default and setting this has no effect.
Maximum length of escaped key and value fields.
value in milliseconds of maximum delay
number of times to retry
value in bytes
value in milliseconds of timeout
Returns true
if the error indicates the transaction may have succeeded, though not in a way the system can verify.
Returns true
if the error indicates the operations in the transactions should be retried because of transient error.
Returns true
if the error indicates the transaction has not committed, though in a way that can be retried.
addend
value with which to perform bitwise and
value to append to the database value
value with which to perform bitwise and
value with which to perform bitwise or
value with which to perform bitwise xor
value to check against database value
value to check against database value
Value to compare with
value to check against database value
value to check against database value
value with which to perform bitwise or
value to which to set the transformed key
value to versionstamp and set
value with which to perform bitwise xor
probability expressed as a percentage between 0 and 100
probability expressed as a percentage between 0 and 100
If set, callbacks from external client libraries can be called from threads created by the FoundationDB client library. Otherwise, callbacks will be called from either the thread used to add the callback or the network thread. Setting this option can improve performance when connected using an external client, but may not be safe to use in all environments. Must be set before setting up the network. WARNING: This feature is considered experimental at this time.
Disable client buggify
Enable client buggify - will make requests randomly fail (intended for client testing)
probability expressed as a percentage between 0 and 100
probability expressed as a percentage between 0 and 100
Number of client threads to be spawned. Each cluster will be serviced by a single client thread.
path to cluster file
Disables logging of client statistics, such as sampled transaction activity.
Prevents connections through the local client, allowing only connections through externally loaded client libraries.
Disables the multi-version client API and instead uses the local client directly. Must be set before setting up the network.
Enables debugging feature to perform run loop profiling. Requires trace logging to be enabled. WARNING: this feature is not recommended for use in production.
Deprecated
This option is set automatically on all clients loaded externally using the multi-version API.
path to directory containing client libraries
path to client library
Transport ID for the child connection
knob_name=knob_value
IP:PORT
[release version],[source version],[protocol version];...
ca bundle
file path
certificates
file path
file path
key passphrase
file path or linker-resolved name
verification pattern
Trace clock source
path to output directory (or NULL for current working directory)
The identifier that will be part of all trace file names
Format of trace files
value of the LogGroup attribute
max total size of trace files
Append this suffix to partially written log files. When a log file is complete, it is renamed to remove the suffix. No separator is added between the file and the suffix. If you want to add a file extension, you should include the separator - e.g. '.tmp' instead of 'tmp' to add the 'tmp' extension.
max size of a single trace output file
Infrequently used. The client has passed a specific row limit and wants that many rows delivered in a single batch. Because of iterator operation in client drivers make request batches transparent to the user, consider WANT_ALL
StreamingMode instead. A row limit must be specified if this mode is used.
The default. The client doesn't know how much of the range it is likely to used and wants different performance concerns to be balanced. Only a small portion of data is transferred to the client initially (in order to minimize costs if the client doesn't read the entire range), and as the caller iterates over more items in the range larger batches will be transferred in order to minimize latency. After enough iterations, the iterator mode will eventually reach the same byte limit as WANT_ALL
Infrequently used. Transfer data in batches large enough to be, in a high-concurrency environment, nearly as efficient as possible. If the client stops iteration early, some disk and network bandwidth may be wasted. The batch size may still be too small to allow a single client to get high throughput from the database, so if that is what you need consider the SERIAL StreamingMode.
Infrequently used. Transfer data in batches sized in between small and large.
Transfer data in batches large enough that an individual client can get reasonable read bandwidth from the database. If the client stops iteration early, considerable disk and network bandwidth may be wasted.
Infrequently used. Transfer data in batches small enough to not be much more expensive than reading individual rows, to minimize cost if iteration stops early.
Client intends to consume the entire range and would like it all transferred as early as possible.
Allows this transaction to read and modify system keys (those that start with the byte 0xFF)
String identifier used to associated this transaction with a throttling group. Must not exceed 16 characters.
Allows get
operations to read from sections of keyspace that have become unreadable because of versionstamp operations. These reads will view versionstamp operations as if they were set operations that did not fill in the versionstamp.
The read version will be committed, and usually will be the latest committed, but might not be the latest committed in the event of a simultaneous fault and misbehaving clock.
The transaction, if not self-conflicting, may be committed a second time after commit succeeds, in the event of a fault
Committing this transaction will bypass the normal load balancing across proxies and go directly to the specifically nominated 'first proxy'.
Optional transaction name
String identifier to be used when tracing or profiling this transaction. The identifier must not exceed 100 characters.
No other transactions will be applied before this transaction within the same commit version.
Addresses returned by get_addresses_for_key include the port when enabled. As of api version 630, this option is enabled by default and setting this has no effect.
This is a write-only transaction which sets the initial configuration. This option is designed for use by database system tools only.
The transaction can read and write to locked databases, and is responsible for checking that it took the lock.
Enables tracing for this transaction and logs results to the client trace logs. The DEBUG_TRANSACTION_IDENTIFIER option must be set before using this option, and client trace logging must be enabled to get log output.
value in milliseconds of maximum delay
The next write performed on this transaction will not generate a write conflict range. As a result, other transactions which read the key(s) being modified by the next write will not conflict with this transaction. Care needs to be taken when using this option on a transaction that is shared between multiple threads. When setting this option, write conflict ranges will be disabled on the next write operation, regardless of what thread it is on.
Specifies that this transaction should be treated as low priority and that default priority transactions will be processed first. Batch priority transactions will also be throttled at load levels smaller than for other types of transactions and may be fully cut off in the event of machine failures. Useful for doing batch work simultaneously with latency-sensitive work
Specifies that this transaction should be treated as highest priority and that lower priority transactions should block behind this one. Use is discouraged outside of low-level tools
Deprecated
The transaction can read from locked databases.
Allows this transaction to read system keys (those that start with the byte 0xFF)
Reads performed by a transaction will not see any prior mutations that occured in that transaction, instead seeing the value which was in the database at the transaction's read version. This option may provide a small performance benefit for the client, but also disables a number of client-side optimizations which are beneficial for transactions which tend to read and write the same keys within a single transaction.
The transaction can retrieve keys that are conflicting with other transactions.
number of times to retry
Sets an identifier for server tracing of this transaction. When committed, this identifier triggers logging when each part of the transaction authority encounters it, which is helpful in diagnosing slowness in misbehaving clusters. The identifier is randomly generated. When there is also a debug_transaction_identifier, both IDs are logged together.
value in bytes
Snapshot read operations will not see the results of writes done in the same transaction. This was the default behavior prior to API version 300.
Snapshot read operations will see the results of writes done in the same transaction. This is the default behavior.
By default, the special key space will only allow users to read from exactly one module (a subspace in the special key space). Use this option to allow reading from zero or more modules. Users who set this option should be prepared for new modules, which may have different behaviors than the modules they're currently reading. For example, a new module might block or return an error.
String identifier used to associated this transaction with a throttling group. Must not exceed 16 characters.
value in milliseconds of timeout
String identifier to be used in the logs when tracing this transaction. The identifier must not exceed 100 characters.
Maximum length of escaped key and value fields.
This option should only be used by tools which change the database configuration.
By default, operations that are performed on a transaction while it is being committed will not only fail themselves, but they will attempt to fail other in-flight operations (such as the commit) as well. This behavior is intended to help developers discover situations where operations could be unintentionally executed after the transaction has been reset. Setting this option removes that protection, causing only the offending operation to fail.
Link to this section Types
Specs
key() :: integer()
Specs
Link to this section Functions
Specs
conflict_range_type_read() :: key()
Used to add a read conflict range
Specs
conflict_range_type_write() :: key()
Used to add a write conflict range
Specs
database_option_datacenter_id() :: key()
Hexadecimal ID
Type: String.t/0
Specify the datacenter ID that was passed to fdbserver processes running in the same datacenter as this client, for better location-aware load balancing.
Specs
database_option_location_cache_size() :: key()
Max location cache entries
Type: integer/0
Set the size of the client location cache. Raising this value can boost performance in very large databases where clients access data in a near-random pattern. Defaults to 100000.
Specs
database_option_machine_id() :: key()
Hexadecimal ID
Type: String.t/0
Specify the machine ID that was passed to fdbserver processes running on the same machine as this client, for better location-aware load balancing.
Specs
database_option_max_watches() :: key()
Max outstanding watches
Type: integer/0
Set the maximum number of watches allowed to be outstanding on a database connection. Increasing this number could result in increased resource usage. Reducing this number will not cancel any outstanding watches. Defaults to 10000 and cannot be larger than 1000000.
Specs
database_option_snapshot_ryw_disable() :: key()
Snapshot read operations will not see the results of writes done in the same transaction. This was the default behavior prior to API version 300.
Specs
database_option_snapshot_ryw_enable() :: key()
Snapshot read operations will see the results of writes done in the same transaction. This is the default behavior.
Specs
database_option_transaction_bypass_unreadable() :: key()
Allows get
operations to read from sections of keyspace that have become unreadable because of versionstamp operations. This sets the bypass_unreadable
option of each transaction created by this database. See the transaction option description for more information.
Specs
database_option_transaction_causal_read_risky() :: key()
The read version will be committed, and usually will be the latest committed, but might not be the latest committed in the event of a simultaneous fault and misbehaving clock.
Specs
database_option_transaction_include_port_in_address() :: key()
Addresses returned by get_addresses_for_key include the port when enabled. As of api version 630, this option is enabled by default and setting this has no effect.
Specs
database_option_transaction_logging_max_field_length() :: key()
Maximum length of escaped key and value fields.
Type: integer/0
Sets the maximum escaped length of key and value fields to be logged to the trace file via the LOG_TRANSACTION option. This sets the transaction_logging_max_field_length
option of each transaction created by this database. See the transaction option description for more information.
Specs
database_option_transaction_max_retry_delay() :: key()
value in milliseconds of maximum delay
Type: integer/0
Set the maximum amount of backoff delay incurred in the call to onError
if the error is retryable. This sets the max_retry_delay
option of each transaction created by this database. See the transaction option description for more information.
Specs
database_option_transaction_retry_limit() :: key()
number of times to retry
Type: integer/0
Set a maximum number of retries after which additional calls to onError
will throw the most recently seen error code. This sets the retry_limit
option of each transaction created by this database. See the transaction option description for more information.
Specs
database_option_transaction_size_limit() :: key()
value in bytes
Type: integer/0
Set the maximum transaction size in bytes. This sets the size_limit
option on each transaction created by this database. See the transaction option description for more information.
Specs
database_option_transaction_timeout() :: key()
value in milliseconds of timeout
Type: integer/0
Set a timeout in milliseconds which, when elapsed, will cause each transaction automatically to be cancelled. This sets the timeout
option of each transaction created by this database. See the transaction option description for more information. Using this option requires that the API version is 610 or higher.
Specs
error_predicate_maybe_committed() :: key()
Returns true
if the error indicates the transaction may have succeeded, though not in a way the system can verify.
Specs
error_predicate_retryable() :: key()
Returns true
if the error indicates the operations in the transactions should be retried because of transient error.
Specs
error_predicate_retryable_not_committed() :: key()
Returns true
if the error indicates the transaction has not committed, though in a way that can be retried.
Specs
mutation_type_add() :: key()
addend
Type: binary/0
Performs an addition of little-endian integers. If the existing value in the database is not present or shorter than param
, it is first extended to the length of param
with zero bytes. If param
is shorter than the existing value in the database, the existing value is truncated to match the length of param
. The integers to be added must be stored in a little-endian representation. They can be signed in two's complement representation or unsigned. You can add to an integer at a known offset in the value by prepending the appropriate number of zero bytes to param
and padding with zero bytes to match the length of the value. However, this offset technique requires that you know the addition will not cause the integer field within the value to overflow.
Specs
mutation_type_and() :: key()
value with which to perform bitwise and
Type: binary/0
Deprecated
Specs
mutation_type_append_if_fits() :: key()
value to append to the database value
Type: binary/0
Appends param
to the end of the existing value already in the database at the given key (or creates the key and sets the value to param
if the key is empty). This will only append the value if the final concatenated value size is less than or equal to the maximum value size (i.e., if it fits). WARNING: No error is surfaced back to the user if the final value is too large because the mutation will not be applied until after the transaction has been committed. Therefore, it is only safe to use this mutation type if one can guarantee that one will keep the total value size under the maximum size.
Specs
mutation_type_bit_and() :: key()
value with which to perform bitwise and
Type: binary/0
Performs a bitwise and
operation. If the existing value in the database is not present, then param
is stored in the database. If the existing value in the database is shorter than param
, it is first extended to the length of param
with zero bytes. If param
is shorter than the existing value in the database, the existing value is truncated to match the length of param
.
Specs
mutation_type_bit_or() :: key()
value with which to perform bitwise or
Type: binary/0
Performs a bitwise or
operation. If the existing value in the database is not present or shorter than param
, it is first extended to the length of param
with zero bytes. If param
is shorter than the existing value in the database, the existing value is truncated to match the length of param
.
Specs
mutation_type_bit_xor() :: key()
value with which to perform bitwise xor
Type: binary/0
Performs a bitwise xor
operation. If the existing value in the database is not present or shorter than param
, it is first extended to the length of param
with zero bytes. If param
is shorter than the existing value in the database, the existing value is truncated to match the length of param
.
Specs
mutation_type_byte_max() :: key()
value to check against database value
Type: binary/0
Performs lexicographic comparison of byte strings. If the existing value in the database is not present, then param
is stored. Otherwise the larger of the two values is then stored in the database.
Specs
mutation_type_byte_min() :: key()
value to check against database value
Type: binary/0
Performs lexicographic comparison of byte strings. If the existing value in the database is not present, then param
is stored. Otherwise the smaller of the two values is then stored in the database.
Specs
mutation_type_compare_and_clear() :: key()
Value to compare with
Type: binary/0
Performs an atomic compare and clear
operation. If the existing value in the database is equal to the given value, then given key is cleared.
Specs
mutation_type_max() :: key()
value to check against database value
Type: binary/0
Performs a little-endian comparison of byte strings. If the existing value in the database is not present or shorter than param
, it is first extended to the length of param
with zero bytes. If param
is shorter than the existing value in the database, the existing value is truncated to match the length of param
. The larger of the two values is then stored in the database.
Specs
mutation_type_min() :: key()
value to check against database value
Type: binary/0
Performs a little-endian comparison of byte strings. If the existing value in the database is not present, then param
is stored in the database. If the existing value in the database is shorter than param
, it is first extended to the length of param
with zero bytes. If param
is shorter than the existing value in the database, the existing value is truncated to match the length of param
. The smaller of the two values is then stored in the database.
Specs
mutation_type_or() :: key()
value with which to perform bitwise or
Type: binary/0
Deprecated
Specs
mutation_type_set_versionstamped_key() :: key()
value to which to set the transformed key
Type: binary/0
Transforms key
using a versionstamp for the transaction. Sets the transformed key in the database to param
. The key is transformed by removing the final four bytes from the key and reading those as a little-Endian 32-bit integer to get a position pos
. The 10 bytes of the key from pos
to pos + 10
are replaced with the versionstamp of the transaction used. The first byte of the key is position 0. A versionstamp is a 10 byte, unique, monotonically (but not sequentially) increasing value for each committed transaction. The first 8 bytes are the committed version of the database (serialized in big-Endian order). The last 2 bytes are monotonic in the serialization order for transactions. WARNING: At this time, versionstamps are compatible with the Tuple layer only in the Java, Python, and Go bindings. Also, note that prior to API version 520, the offset was computed from only the final two bytes rather than the final four bytes.
Specs
mutation_type_set_versionstamped_value() :: key()
value to versionstamp and set
Type: binary/0
Transforms param
using a versionstamp for the transaction. Sets the key
given to the transformed param
. The parameter is transformed by removing the final four bytes from param
and reading those as a little-Endian 32-bit integer to get a position pos
. The 10 bytes of the parameter from pos
to pos + 10
are replaced with the versionstamp of the transaction used. The first byte of the parameter is position 0. A versionstamp is a 10 byte, unique, monotonically (but not sequentially) increasing value for each committed transaction. The first 8 bytes are the committed version of the database (serialized in big-Endian order). The last 2 bytes are monotonic in the serialization order for transactions. WARNING: At this time, versionstamps are compatible with the Tuple layer only in the Java, Python, and Go bindings. Also, note that prior to API version 520, the versionstamp was always placed at the beginning of the parameter rather than computing an offset.
Specs
mutation_type_xor() :: key()
value with which to perform bitwise xor
Type: binary/0
Deprecated
Specs
network_option_buggify_disable() :: key()
Specs
network_option_buggify_enable() :: key()
Specs
network_option_buggify_section_activated_probability() :: key()
probability expressed as a percentage between 0 and 100
Type: integer/0
Set the probability of a BUGGIFY section being active for the current execution. Only applies to code paths first traversed AFTER this option is changed.
Specs
network_option_buggify_section_fired_probability() :: key()
probability expressed as a percentage between 0 and 100
Type: integer/0
Set the probability of an active BUGGIFY section being fired
Specs
network_option_callbacks_on_external_threads() :: key()
If set, callbacks from external client libraries can be called from threads created by the FoundationDB client library. Otherwise, callbacks will be called from either the thread used to add the callback or the network thread. Setting this option can improve performance when connected using an external client, but may not be safe to use in all environments. Must be set before setting up the network. WARNING: This feature is considered experimental at this time.
Specs
network_option_client_buggify_disable() :: key()
Disable client buggify
Specs
network_option_client_buggify_enable() :: key()
Enable client buggify - will make requests randomly fail (intended for client testing)
Specs
network_option_client_buggify_section_activated_probability() :: key()
probability expressed as a percentage between 0 and 100
Type: integer/0
Set the probability of a CLIENT_BUGGIFY section being active for the current execution.
Specs
network_option_client_buggify_section_fired_probability() :: key()
probability expressed as a percentage between 0 and 100
Type: integer/0
Set the probability of an active CLIENT_BUGGIFY section being fired. A section will only fire if it was activated
Specs
network_option_client_threads_per_version() :: key()
Number of client threads to be spawned. Each cluster will be serviced by a single client thread.
Type: integer/0
Spawns multiple worker threads for each version of the client that is loaded. Setting this to a number greater than one implies disable_local_client.
Specs
network_option_cluster_file() :: key()
path to cluster file
Type: String.t/0
Deprecated
Specs
network_option_disable_client_statistics_logging() :: key()
Disables logging of client statistics, such as sampled transaction activity.
Specs
network_option_disable_local_client() :: key()
Prevents connections through the local client, allowing only connections through externally loaded client libraries.
Specs
network_option_disable_multi_version_client_api() :: key()
Disables the multi-version client API and instead uses the local client directly. Must be set before setting up the network.
Specs
network_option_enable_run_loop_profiling() :: key()
Enables debugging feature to perform run loop profiling. Requires trace logging to be enabled. WARNING: this feature is not recommended for use in production.
Specs
network_option_enable_slow_task_profiling() :: key()
Deprecated
Specs
network_option_external_client() :: key()
This option is set automatically on all clients loaded externally using the multi-version API.
Specs
network_option_external_client_directory() :: key()
path to directory containing client libraries
Type: String.t/0
Searches the specified path for dynamic libraries and adds them to the list of client libraries for use by the multi-version client API. Must be set before setting up the network.
Specs
network_option_external_client_library() :: key()
path to client library
Type: String.t/0
Adds an external client library for use by the multi-version client API. Must be set before setting up the network.
Specs
network_option_external_client_transport_id() :: key()
Transport ID for the child connection
Type: integer/0
This option tells a child on a multiversion client what transport ID to use.
Specs
network_option_knob() :: key()
knob_name=knob_value
Type: String.t/0
Set internal tuning or debugging knobs
Specs
network_option_local_address() :: key()
IP:PORT
Type: String.t/0
Deprecated
Specs
network_option_supported_client_versions() :: key()
[release version],[source version],[protocol version];...
Type: String.t/0
This option is set automatically to communicate the list of supported clients to the active client.
Specs
network_option_tls_ca_bytes() :: key()
ca bundle
Type: binary/0
Set the ca bundle
Specs
network_option_tls_ca_path() :: key()
file path
Type: String.t/0
Set the file from which to load the certificate authority bundle
Specs
network_option_tls_cert_bytes() :: key()
certificates
Type: binary/0
Set the certificate chain
Specs
network_option_tls_cert_path() :: key()
file path
Type: String.t/0
Set the file from which to load the certificate chain
Specs
network_option_tls_key_bytes() :: key()
key
Type: binary/0
Set the private key corresponding to your own certificate
Specs
network_option_tls_key_path() :: key()
file path
Type: String.t/0
Set the file from which to load the private key corresponding to your own certificate
Specs
network_option_tls_password() :: key()
key passphrase
Type: String.t/0
Set the passphrase for encrypted private key. Password should be set before setting the key for the password to be used.
Specs
network_option_tls_plugin() :: key()
file path or linker-resolved name
Type: String.t/0
Deprecated
Specs
network_option_tls_verify_peers() :: key()
verification pattern
Type: binary/0
Set the peer certificate field verification criteria
Specs
network_option_trace_clock_source() :: key()
Trace clock source
Type: String.t/0
Select clock source for trace files. now (the default) or realtime are supported.
Specs
network_option_trace_enable() :: key()
path to output directory (or NULL for current working directory)
Type: String.t/0
Enables trace output to a file in a directory of the clients choosing
Specs
network_option_trace_file_identifier() :: key()
The identifier that will be part of all trace file names
Type: String.t/0
Once provided, this string will be used to replace the port/PID in the log file names.
Specs
network_option_trace_format() :: key()
Format of trace files
Type: String.t/0
Select the format of the log files. xml (the default) and json are supported.
Specs
network_option_trace_log_group() :: key()
value of the LogGroup attribute
Type: String.t/0
Sets the 'LogGroup' attribute with the specified value for all events in the trace output files. The default log group is 'default'.
Specs
network_option_trace_max_logs_size() :: key()
max total size of trace files
Type: integer/0
Sets the maximum size of all the trace output files put together. This value should be in the range [0, INT64_MAX]
. If the value is set to 0, there is no limit on the total size of the files. The default is a maximum size of 104,857,600 bytes. If the default roll size is used, this means that a maximum of 10 trace files will be written at a time.
Specs
network_option_trace_partial_file_suffix() :: key()
Append this suffix to partially written log files. When a log file is complete, it is renamed to remove the suffix. No separator is added between the file and the suffix. If you want to add a file extension, you should include the separator - e.g. '.tmp' instead of 'tmp' to add the 'tmp' extension.
Type: String.t/0
Specs
network_option_trace_roll_size() :: key()
max size of a single trace output file
Type: integer/0
Sets the maximum size in bytes of a single trace output file. This value should be in the range [0, INT64_MAX]
. If the value is set to 0, there is no limit on individual file size. The default is a maximum size of 10,485,760 bytes.
Specs
streaming_mode_exact() :: key()
Infrequently used. The client has passed a specific row limit and wants that many rows delivered in a single batch. Because of iterator operation in client drivers make request batches transparent to the user, consider WANT_ALL
StreamingMode instead. A row limit must be specified if this mode is used.
Specs
streaming_mode_iterator() :: key()
The default. The client doesn't know how much of the range it is likely to used and wants different performance concerns to be balanced. Only a small portion of data is transferred to the client initially (in order to minimize costs if the client doesn't read the entire range), and as the caller iterates over more items in the range larger batches will be transferred in order to minimize latency. After enough iterations, the iterator mode will eventually reach the same byte limit as WANT_ALL
Specs
streaming_mode_large() :: key()
Infrequently used. Transfer data in batches large enough to be, in a high-concurrency environment, nearly as efficient as possible. If the client stops iteration early, some disk and network bandwidth may be wasted. The batch size may still be too small to allow a single client to get high throughput from the database, so if that is what you need consider the SERIAL StreamingMode.
Specs
streaming_mode_medium() :: key()
Infrequently used. Transfer data in batches sized in between small and large.
Specs
streaming_mode_serial() :: key()
Transfer data in batches large enough that an individual client can get reasonable read bandwidth from the database. If the client stops iteration early, considerable disk and network bandwidth may be wasted.
Specs
streaming_mode_small() :: key()
Infrequently used. Transfer data in batches small enough to not be much more expensive than reading individual rows, to minimize cost if iteration stops early.
Specs
streaming_mode_want_all() :: key()
Client intends to consume the entire range and would like it all transferred as early as possible.
Specs
transaction_option_access_system_keys() :: key()
Allows this transaction to read and modify system keys (those that start with the byte 0xFF)
Specs
transaction_option_auto_throttle_tag() :: key()
String identifier used to associated this transaction with a throttling group. Must not exceed 16 characters.
Type: String.t/0
Adds a tag to the transaction that can be used to apply manual or automatic targeted throttling. At most 5 tags can be set on a transaction.
Specs
transaction_option_bypass_unreadable() :: key()
Allows get
operations to read from sections of keyspace that have become unreadable because of versionstamp operations. These reads will view versionstamp operations as if they were set operations that did not fill in the versionstamp.
Specs
transaction_option_causal_read_disable() :: key()
Specs
transaction_option_causal_read_risky() :: key()
The read version will be committed, and usually will be the latest committed, but might not be the latest committed in the event of a simultaneous fault and misbehaving clock.
Specs
transaction_option_causal_write_risky() :: key()
The transaction, if not self-conflicting, may be committed a second time after commit succeeds, in the event of a fault
Specs
transaction_option_check_writes_enable() :: key()
Specs
transaction_option_commit_on_first_proxy() :: key()
Committing this transaction will bypass the normal load balancing across proxies and go directly to the specifically nominated 'first proxy'.
Specs
transaction_option_debug_dump() :: key()
Specs
transaction_option_debug_retry_logging() :: key()
Optional transaction name
Type: String.t/0
Specs
transaction_option_debug_transaction_identifier() :: key()
String identifier to be used when tracing or profiling this transaction. The identifier must not exceed 100 characters.
Type: String.t/0
Sets a client provided identifier for the transaction that will be used in scenarios like tracing or profiling. Client trace logging or transaction profiling must be separately enabled.
Specs
transaction_option_durability_datacenter() :: key()
Specs
transaction_option_durability_dev_null_is_web_scale() :: key()
Deprecated
Specs
transaction_option_durability_risky() :: key()
Specs
transaction_option_first_in_batch() :: key()
No other transactions will be applied before this transaction within the same commit version.
Specs
transaction_option_include_port_in_address() :: key()
Addresses returned by get_addresses_for_key include the port when enabled. As of api version 630, this option is enabled by default and setting this has no effect.
Specs
transaction_option_initialize_new_database() :: key()
This is a write-only transaction which sets the initial configuration. This option is designed for use by database system tools only.
Specs
transaction_option_lock_aware() :: key()
The transaction can read and write to locked databases, and is responsible for checking that it took the lock.
Specs
transaction_option_log_transaction() :: key()
Enables tracing for this transaction and logs results to the client trace logs. The DEBUG_TRANSACTION_IDENTIFIER option must be set before using this option, and client trace logging must be enabled to get log output.
Specs
transaction_option_max_retry_delay() :: key()
value in milliseconds of maximum delay
Type: integer/0
Set the maximum amount of backoff delay incurred in the call to onError
if the error is retryable. Defaults to 1000 ms. Valid parameter values are [0, INT_MAX]
. If the maximum retry delay is less than the current retry delay of the transaction, then the current retry delay will be clamped to the maximum retry delay. Prior to API version 610, like all other transaction options, the maximum retry delay must be reset after a call to onError
. If the API version is 610 or greater, the retry limit is not reset after an onError
call. Note that at all API versions, it is safe and legal to set the maximum retry delay each time the transaction begins, so most code written assuming the older behavior can be upgraded to the newer behavior without requiring any modification, and the caller is not required to implement special logic in retry loops to only conditionally set this option.
Specs
transaction_option_next_write_no_write_conflict_range() :: key()
The next write performed on this transaction will not generate a write conflict range. As a result, other transactions which read the key(s) being modified by the next write will not conflict with this transaction. Care needs to be taken when using this option on a transaction that is shared between multiple threads. When setting this option, write conflict ranges will be disabled on the next write operation, regardless of what thread it is on.
Specs
transaction_option_priority_batch() :: key()
Specifies that this transaction should be treated as low priority and that default priority transactions will be processed first. Batch priority transactions will also be throttled at load levels smaller than for other types of transactions and may be fully cut off in the event of machine failures. Useful for doing batch work simultaneously with latency-sensitive work
Specs
transaction_option_priority_system_immediate() :: key()
Specifies that this transaction should be treated as highest priority and that lower priority transactions should block behind this one. Use is discouraged outside of low-level tools
Specs
transaction_option_read_ahead_disable() :: key()
Deprecated
Specs
transaction_option_read_lock_aware() :: key()
The transaction can read from locked databases.
Specs
transaction_option_read_system_keys() :: key()
Allows this transaction to read system keys (those that start with the byte 0xFF)
Specs
transaction_option_read_your_writes_disable() :: key()
Reads performed by a transaction will not see any prior mutations that occured in that transaction, instead seeing the value which was in the database at the transaction's read version. This option may provide a small performance benefit for the client, but also disables a number of client-side optimizations which are beneficial for transactions which tend to read and write the same keys within a single transaction.
Specs
transaction_option_report_conflicting_keys() :: key()
The transaction can retrieve keys that are conflicting with other transactions.
Specs
transaction_option_retry_limit() :: key()
number of times to retry
Type: integer/0
Set a maximum number of retries after which additional calls to onError
will throw the most recently seen error code. Valid parameter values are [-1, INT_MAX]
. If set to -1, will disable the retry limit. Prior to API version 610, like all other transaction options, the retry limit must be reset after a call to onError
. If the API version is 610 or greater, the retry limit is not reset after an onError
call. Note that at all API versions, it is safe and legal to set the retry limit each time the transaction begins, so most code written assuming the older behavior can be upgraded to the newer behavior without requiring any modification, and the caller is not required to implement special logic in retry loops to only conditionally set this option.
Specs
transaction_option_server_request_tracing() :: key()
Sets an identifier for server tracing of this transaction. When committed, this identifier triggers logging when each part of the transaction authority encounters it, which is helpful in diagnosing slowness in misbehaving clusters. The identifier is randomly generated. When there is also a debug_transaction_identifier, both IDs are logged together.
Specs
transaction_option_size_limit() :: key()
value in bytes
Type: integer/0
Set the transaction size limit in bytes. The size is calculated by combining the sizes of all keys and values written or mutated, all key ranges cleared, and all read and write conflict ranges. (In other words, it includes the total size of all data included in the request to the cluster to commit the transaction.) Large transactions can cause performance problems on FoundationDB clusters, so setting this limit to a smaller value than the default can help prevent the client from accidentally degrading the cluster's performance. This value must be at least 32 and cannot be set to higher than 10,000,000, the default transaction size limit.
Specs
transaction_option_snapshot_ryw_disable() :: key()
Snapshot read operations will not see the results of writes done in the same transaction. This was the default behavior prior to API version 300.
Specs
transaction_option_snapshot_ryw_enable() :: key()
Snapshot read operations will see the results of writes done in the same transaction. This is the default behavior.
Specs
transaction_option_special_key_space_relaxed() :: key()
By default, the special key space will only allow users to read from exactly one module (a subspace in the special key space). Use this option to allow reading from zero or more modules. Users who set this option should be prepared for new modules, which may have different behaviors than the modules they're currently reading. For example, a new module might block or return an error.
Specs
transaction_option_tag() :: key()
String identifier used to associated this transaction with a throttling group. Must not exceed 16 characters.
Type: String.t/0
Adds a tag to the transaction that can be used to apply manual targeted throttling. At most 5 tags can be set on a transaction.
Specs
transaction_option_timeout() :: key()
value in milliseconds of timeout
Type: integer/0
Set a timeout in milliseconds which, when elapsed, will cause the transaction automatically to be cancelled. Valid parameter values are [0, INT_MAX]
. If set to 0, will disable all timeouts. All pending and any future uses of the transaction will throw an exception. The transaction can be used again after it is reset. Prior to API version 610, like all other transaction options, the timeout must be reset after a call to onError
. If the API version is 610 or greater, the timeout is not reset after an onError
call. This allows the user to specify a longer timeout on specific transactions than the default timeout specified through the transaction_timeout
database option without the shorter database timeout cancelling transactions that encounter a retryable error. Note that at all API versions, it is safe and legal to set the timeout each time the transaction begins, so most code written assuming the older behavior can be upgraded to the newer behavior without requiring any modification, and the caller is not required to implement special logic in retry loops to only conditionally set this option.
Specs
transaction_option_transaction_logging_enable() :: key()
String identifier to be used in the logs when tracing this transaction. The identifier must not exceed 100 characters.
Type: String.t/0
Deprecated
Specs
transaction_option_transaction_logging_max_field_length() :: key()
Maximum length of escaped key and value fields.
Type: integer/0
Sets the maximum escaped length of key and value fields to be logged to the trace file via the LOG_TRANSACTION option, after which the field will be truncated. A negative value disables truncation.
Specs
transaction_option_use_provisional_proxies() :: key()
This option should only be used by tools which change the database configuration.
Specs
transaction_option_used_during_commit_protection_disable() :: key()
By default, operations that are performed on a transaction while it is being committed will not only fail themselves, but they will attempt to fail other in-flight operations (such as the commit) as well. This behavior is intended to help developers discover situations where operations could be unintentionally executed after the transaction has been reset. Setting this option removes that protection, causing only the offending operation to fail.