This page documents system variables related to the Mroonga storage engine. See Server System Variables for a complete list of system variables and instructions on setting them.

See also the Full list of MariaDB options, system and status variables.

mroonga_action_on_fulltext_query_error

• Description: Action to take when encountering a Mroonga fulltext error.
  • ERROR: Report an error without logging.
  • ERROR_AND_LOG: Report an error with logging (the default)
  • IGNORE: No logging or reporting - the error is ignored.
  • IGNORE_AND_LOG: Log the error without reporting it.
• Commandline: --mroonga-action-on-fulltext-query-error=value
• Scope: Global, Session
• Dynamic: Yes
• Data Type: enum
• Default Value: ERROR_AND_LOG

mroonga_boolean_mode_syntax_flags

• Description: Flags to customize syntax in BOOLEAN MODE searches. Available flags:
  • DEFAULT: (=SYNTAX_QUERY,ALLOW_LEADING_NOT)
  • ALLOW_COLUMN: Allows COLUMN:... syntax in query syntax, an incompatible change to the regular BOOLEAN MODE syntax. Permits multiple indexes in one MATCH () AGAINST (). Can be used in other operations besides full-text search, such as equal, and prefix search. See Groonga query syntax for more details.
  • ALLOW_LEADING_NOT Permits using the NOT_INCLUDED_KEYWORD syntax in the query syntax.
  • ALLOW_UPDATE: Permits updating values with the COLUMN:=NEW_VALUE syntax in the query syntax.
  • SYNTAX_QUERY: Mroonga will use Groonga's query syntax, compatible with MariaDB's BOOLEAN MODE syntax. Unless SYNTAX_SCRIPT is specified, this mode is always in use.
  • SYNTAX_SCRIPT: Mroonga will use Groonga's script syntax, a JavaScript-like syntax. If both SYNTAX_QUERY and SYNTAX_SCRIPT are specified, SYNTAX_SCRIPT will take precedence..
• Commandline: --mroonga-boolean-mode-syntax-flags=value
• Scope: Global, Session
• Dynamic: Yes
• Data Type: enum
• Default Value: DEFAULT

mroonga_database_path_prefix

• Description: The database path prefix.
• Commandline: --mroonga-database-path-prefix=value
• Scope: Global
• Dynamic: Yes
• Data Type: string
• Default Value: (Empty)

mroonga_default_parser

• Description: The fulltext default parser, for example TokenBigramSplitSymbolAlphaDigit or TokenBigram (the default). See the list of options at Mroonga Overview:Parser. Deprecated since Mroonga 5.04, use mroonga_default_tokenizer instead.
• Commandline: --mroonga-default-parser=value
• Scope: Global
• Dynamic: Yes
• Data Type: string
• Default Value: TokenBigram

mroonga_default_tokenizer

• Description: The fulltext default parser, for example TokenBigramSplitSymbolAlphaDigit or TokenBigram (the default). See the list of options at Mroonga Overview:Parser.
• Commandline: --mroonga-default-tokenizer=value
• Scope: Global, Session
• Dynamic: Yes
• Data Type: string
• Default Value: TokenBigram
• Introduced: MariaDB 10.1.6, Mroonga 5.0.4

mroonga_default_wrapper_engine

• Description: The default engine for wrapper mode.
• Commandline: --mroonga-default-wrapper-engine=value
• Scope: Global
• Dynamic: No
• Data Type: string
• Default Value: (Empty)

mroonga_dry_write

• Description: If set to on, (off is default), data is not actually written to the Groonga database. Only really useful to change for benchmarking.
• Commandline: --mroonga-dry-write[={0|1}]
• Scope: Global, Session
• Dynamic: Yes
• Data Type: boolean
• Default Value: off

mroonga_enable_operations_recording

• Description: Whether recording operations for recovery to the Groonga database is enabled (default) or not. Requires reopening the database with FLUSH TABLES after changing the variable.
• Commandline: --mroonga-enable-operations-recording={0|1}
• Scope: Global
• Dynamic: Yes
• Data Type: boolean
• Default Value: ON
• Introduced: MariaDB 10.2.11, MariaDB 10.1.29

mroonga_enable_optimization

• Description: If set to on (the default), optimization is enabled. Only really useful to change for benchmarking.
• Commandline: --mroonga-enable-optimization={0|1}
• Scope: Global, Session
• Dynamic: Yes
• Data Type: boolean
• Default Value: on

mroonga_libgroonga_embedded

• Description: Whether libgroonga is embedded or not.
• Commandline: None
• Scope: Global
• Dynamic: No
• Data Type: boolean
• Default Value: ON
• Introduced: MariaDB 10.1.6

mroonga_libgroonga_support_lz4

• Description: Whether libgroonga supports lz4 or not.
• Commandline: None
• Scope: Global
• Dynamic: No
• Data Type: boolean
• Default Value: OFF
• Introduced: MariaDB 10.0.17

mroonga_libgroonga_support_zlib

• Description: Whether libgroonga supports zlib or not.
• Commandline: None
• Scope: Global
• Dynamic: No
• Data Type: boolean
• Default Value: ON

mroonga_libgroonga_support_zstd

• Description: Whether libgroonga supports Zstandard or not.
• Commandline: None
• Scope: Global
• Dynamic: No
• Data Type: boolean
• Default Value: OFF
• Introduced: MariaDB 10.2.11, MariaDB 10.1.29

mroonga_libgroonga_version

• Description: Groonga library version.
• Commandline: None
• Scope: Global
• Dynamic: No
• Data Type: string

mroonga_lock_timeout

• Description: Lock timeout used in Groonga.
• Commandline: <<code>>--mroonga-lock-timeout=#</code>>
• Scope: Global
• Dynamic: Yes
• Data Type: numeric
• Default Value: 900000
• Range: -1 to 2147483647

mroonga_log_file

• Description: Name and path of the Mroonga log file.
• Commandline: --mroonga-log-file=value
• Scope: Global
• Dynamic: Yes
• Data Type: string
• Default Value: groonga.log

mroonga_log_level

• Description: Mroonga log file output level, which determines what is logged. Valid levels include:
  • NONE No output.
  • EMERG: Only emergency error messages, such as database corruption.
  • ALERT: Alert messages, such as internal errors.
  • CRIT : Critical error messages, such as deadlocks.
  • ERROR : Errors, such as API errors.
  • WARNING: Warnings, such as invalid arguments.
  • NOTICE: Notices, such as a change in configuration or a status change.
  • INFO: Information messages, such as file system operations.
  • DEBUG: Debug messages, suggested for developers or testers.
  • DUMP: Dump messages.
• Commandline: --mroonga-log-level=value
• Scope: Global
• Dynamic: Yes
• Data Type: enum
• Default Value: NOTICE

mroonga_match_escalation_threshold

• Description: The threshold to determine whether the match method is escalated. -1 means never escalate.
• Commandline: --mroonga-match-escalation-threshold=#
• Scope: Global, Session
• Dynamic: Yes
• Data Type: numeric
• Default Value: 0
• Range: -1 to 9223372036854775807

mroonga_max_n_records_for_estimate

• Description: The max number of records to estimate the number of matched records
• Commandline: --mroonga-max-n-records-for-estimate=#
• Scope: Global, Session
• Dynamic: Yes
• Data Type: numeric
• Default Value: 1000
• Range: -1 to 2147483647
• Introduced: MariaDB 10.0.18, Mroonga 5.0.2

mroonga_query_log_file

• Description: Query log file for Mroonga.
• Commandline: --mroonga-query-log-file=filename
• Scope: Global
• Dynamic: Yes
• Data Type: string
• Default Value: (Empty string)
• Introduced: MariaDB 10.2.11, MariaDB 10.1.29

mroonga_vector_column_delimiter

• Description: Delimiter to use when outputting a vector column. The default is a white space.
• Commandline: --mroonga-vector-column-delimiter=value
• Scope: Global
• Dynamic: Yes
• Data Type: string
• Default Value: (white space)

mroonga_version

• Description: Mroonga version
• Commandline: None
• Scope: Global
• Dynamic: No
• Data Type: string