Options

Constructors

this

this()

Create the internal option object

Destructor

~this

~this()

Destroy any valid option pointer

Members

Classes

AFilterPolicy

class AFilterPolicy

User Filter Policy

BloomFilterPolicy

class BloomFilterPolicy

Bloom filter

Comparator

class Comparator

User Comparator, this is a default string comparator

Environment

class Environment

Environment object, API only has deault environment

LRUCache

class LRUCache

Cache Object, can only set size

Properties

block_restart_interval

int block_restart_interval [@property setter]

Number of keys between restart points for delta encoding of keys. This parameter can be changed dynamically. Most clients should leave this parameter alone.

block_size

size_t block_size [@property setter]

Approximate size of user data packed per block. Note that the block size specified here corresponds to uncompressed data. The actual size of the unit read from disk may be smaller if compression is enabled. This parameter can be changed dynamically.

cache

Cache cache [@property setter]

Control over blocks (user data is stored in a set of blocks, and a block is the unit of reading from disk).

comparator

Comparator comparator [@property setter]

Comparator used to define the order of keys in the table. Default: a comparator that uses lexicographic byte-wise ordering

compression

int compression [@property setter]

Compress blocks using the specified compression algorithm. This parameter can be changed dynamically.

create_if_missing

bool create_if_missing [@property setter]

If true, the database will be created if it is missing. Default: false

env

Environment env [@property setter]

Use the specified object to interact with the environment, e.g. to read/write files, schedule background work, etc. Default: Environment()

error_if_missing

bool error_if_missing [@property setter]

If true, an error is raised if the database already exists. Default: false

filter_policy

FilterPolicy filter_policy [@property setter]

If non-NULL, use the specified filter policy to reduce disk reads. Many applications will benefit from passing the result of BloomFilterPolicy here.

max_open_files

int max_open_files [@property setter]

Number of open files that can be used by the DB. You may need to increase this if your database has a large working set (budget one open file per 2MB of working set).

paranoid_checks

bool paranoid_checks [@property setter]

If true, the implementation will do aggressive checking of the data it is processing and will stop early if it detects any errors. This may have unforeseen ramifications: for example, a corruption of one DB entry may cause a large number of entries to become unreadable or for the entire DB to become unopenable. Default: false

valid

bool valid [@property getter]

indicates if the option has been created

write_buffer_size

size_t write_buffer_size [@property setter]

Parameters that affect performance Amount of data to build up in memory (backed by an unsorted log on disk) before converting to a sorted on-disk file.

• Options
• ReadOptions
• WriteOptions

• DefaultReadOptions