text_index_* MergeTree table settings

These settings are available in system.merge_tree_settings and are autogenerated from the ClickHouse snapshot.

text_index_dictionary_block_frontcoding_compression

Default front-coding compression for text index dictionary blocks. Can be overridden by explicit dictionary_block_frontcoding_compression index argument.

text_index_dictionary_block_size

Default dictionary block size for text indexes. Can be overridden by explicit dictionary_block_size index argument.

text_index_max_memory_usage_before_flush

Maximum estimated memory retained by a text index builder before flushing a temporary segment.

text_index_max_processed_tokens_before_flush

Maximum number of processed tokens accumulated by a text index builder before flushing a temporary segment.

text_index_posting_list_block_size

Default posting list block size for text indexes (rows). Can be overridden by explicit posting_list_block_size index argument.

text_index_posting_list_codec

Default posting list codec for text indexes. One of none, bitpacking, pfor. Can be overridden by explicit posting_list_codec index argument.

text_index_serialization_version

The preferred on-disk serialization format version for writing text indexes.

The setting is a preference rather than a hard constraint: if the configured version cannot represent an index, a newer version that can represent it is chosen automatically, and writing a text index never fails because of this setting.

During a rolling upgrade, pin the format with the profile-level compatibility setting on the already upgraded servers, so that they keep writing the format that older servers can still read.

Possible values:

• v0_initial — The original format. Does not persist the posting list codec type.
• v1_with_codec — Persists the posting list codec type in the text index header.
• v2_with_positions — Persists token positions for indexes with support_phrase_search.