Limitations v7.4
This section is adapted from the WarehousePG v7.x documentation
This topic lists limitations and maximums for WarehousePG full text search objects.
The current limitations of WarehousePG's text search features are:
- The
tsvectorandtsquerytypes are not supported in the distribution key for a WarehousePG table - The length of each lexeme must be less than 2K bytes
- The length of a
tsvector(lexemes + positions) must be less than 1 megabyte - The match distance in a
<N>(FOLLOWED BY)tsqueryoperator cannot be more than 16,384 - The number of lexemes must be less than 264
- Position values in
tsvectormust be greater than 0 and no more than 16,383 - No more than 256 positions per lexeme
- The number of nodes (lexemes + operators) in a tsquery must be less than 32,768
For comparison, the PostgreSQL 8.1 documentation contained 10,441 unique words, a total of 335,420 words, and the most frequent word "postgresql" was mentioned 6,127 times in 655 documents.
Another example — the PostgreSQL mailing list archives contained 910,989 unique words with 57,491,343 lexemes in 461,020 messages.
Parent topic: Using Full Text Search