[sqlite] Querying nextchar extension
I was thinking of dynamically building up the strings using the `nextchar` extension but your example works just fine. On Fri, Sep 18, 2015 at 9:52 AM, Igor Tandetnik wrote: > On 9/18/2015 9:05 AM, Charles Leifer wrote: > >> As a challenge I was curious how one would write a recursive CTE to take a >> substring and recursively calculate all possible matches. I realize I >> could >> just use 'LIKE xxx%' to accomplish the same, but if anyone has any >> thoughts >> on writing such a query I'd love to hear them! >> > > Something along these lines (untested): > > select group_concat(substr(word, length(:prefix)+1, 1), '') > from words where substr(word, 1, length(:prefix)) = :prefix > > Not sure what recursive CTE has to do with it - what is there to recurse > over? > -- > Igor Tandetnik > > ___ > sqlite-users mailing list > sqlite-users at mailinglists.sqlite.org > http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users >
[sqlite] Querying nextchar extension
On 9/18/2015 9:05 AM, Charles Leifer wrote: > As a challenge I was curious how one would write a recursive CTE to take a > substring and recursively calculate all possible matches. I realize I could > just use 'LIKE xxx%' to accomplish the same, but if anyone has any thoughts > on writing such a query I'd love to hear them! Something along these lines (untested): select group_concat(substr(word, length(:prefix)+1, 1), '') from words where substr(word, 1, length(:prefix)) = :prefix Not sure what recursive CTE has to do with it - what is there to recurse over? -- Igor Tandetnik
[sqlite] Querying nextchar extension
I've been playing around a bit with the `nextchar` extension and I must say it's pretty neat! Basically I create a table named `words` with a single TEXT column named `word` and populate it with a dictionary file. Then I can run: SELECT nextchar('partial word', 'words', 'word'); And it will return a string containing all the characters that could possibly be the "next char" of a valid word. For example: nextchar('foota') -> 'g' nextchar('footag') -> 'e' nextchar('footage') -> no result As a challenge I was curious how one would write a recursive CTE to take a substring and recursively calculate all possible matches. I realize I could just use 'LIKE xxx%' to accomplish the same, but if anyone has any thoughts on writing such a query I'd love to hear them!