Re: string_to_array eats too much memory?

>> tsvector size should not be greater than 1Mb however.
> 
> Is this documented somewhere? Also I noticed that tsearch2 treats ":"
> as a special character. Are there any special characters? If so where
> are they documented?
http://www.sai.msu.su/~megera/wiki/Tsearch_V2_in_Brief
Limitations
13.1 2048 bytes for lexems13.2 ts_vector has limit about 1Mb. Exact value depends on    quantity of position
information.If there is no any position                information, then sum of length of lexem must be less than 1Mb,
             otherwise, sum of length of and pos. info.                Positional information uses 2 bytes per each
positionand 2 bytes per lexem with pos info. The number of                lexems is limited by 4^32, so in practice
it'sunlimited.13.3 ts_query:                Number of entries (nodes, i.e sum of lexems and operation)
islimited: internal representation is in polish notation                and position of one operand is pointed by int2,
soit's                rather soft limit.                In any case, low range of limit - 32768 nodes.    Notice:
ts_querydoesn't designed for storing in table and                is optimized for speed, not for size.13.4 Positional
informationin ts_vector:    13.4.1 Value of position may not be greater than 2^14 (16384),                       any
valuegreater than this limit will be replaced                       by 16383.    13.4.2 Only 256 positional info per
lexem.


Some useful articles
http://www.sai.msu.su/~megera/postgres/gist/tsearch/V2/docs/HOWTO-parser-tsearch2.html
http://www.sai.msu.su/~megera/postgres/gist/tsearch/V2/docs/custom-dict.html


-- 
Teodor Sigaev                                   E-mail: teodor@sigaev.ru
  WWW: http://www.sigaev.ru/