PostgreSQL
12.11. Limitations
The current limitations of PostgreSQL’s text search features are:
-
The length of each lexeme must be less than 2 kilobytes
-
The length of a
tsvector
(lexemes + positions) must be less than 1 megabyte -
The number of lexemes must be less than 264
-
Position values in
tsvector
must be greater than 0 and no more than 16,383 -
The match distance in a
<`
N>` (FOLLOWED BY)
tsquery
operator cannot be more than 16,384 -
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 “[.quote]#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.
Prev | Up | Next |
---|---|---|
12.10. psql Support |
Chapter 13. Concurrency Control |
Submit correction
If you see anything in the documentation that is not correct, does not match your experience with the particular feature or requires further clarification, please use this form to report a documentation issue.
Copyright © 1996-2023 The PostgreSQL Global Development Group