Re: [sqlite] fast string prefix matching

2010-08-18 Thread Igor Tandetnik
Doug Reeder wrote: > Does SQLite treat strings as sequences of opaque 16-bit values, except > for the wildcard operators for LIKE and GLOB? Does it care about > surrogate code points? Does it care about FDD0 to FDEF ? SQLite knows something about surrogate pairs - this knowledge is required in

Re: [sqlite] fast string prefix matching

2010-08-18 Thread Simon Slavin
On 18 Aug 2010, at 7:26am, Doug Reeder wrote: > Does SQLite treat strings as sequences of opaque 16-bit values, except > for the wildcard operators for LIKE and GLOB? Does it care about > surrogate code points? Does it care about FDD0 to FDEF ? The first: opaque. It doesn't understand any

Re: [sqlite] fast string prefix matching

2010-08-17 Thread Doug Reeder
On Aug 17, 2010, at 9:28 PM, Igor Tandetnik wrote: > Doug Reeder wrote: >> I need to search for string prefix matches; for example given the >> path 'PP', >> I need to find 'PPA', 'PPBJQ', and 'PPz'. (The character set is all >> characters greater than or equal to 'A', and is case-sensitive.)

Re: [sqlite] fast string prefix matching

2010-08-17 Thread Igor Tandetnik
Doug Reeder wrote: > I need to search for string prefix matches; for example given the path 'PP', > I need to find 'PPA', 'PPBJQ', and 'PPz'. (The character set is all > characters greater than or equal to 'A', and is case-sensitive.) A > statement that does exactly what I want is > > "UPDATE

[sqlite] fast string prefix matching

2010-08-17 Thread Doug Reeder
I need to search for string prefix matches; for example given the path 'PP', I need to find 'PPA', 'PPBJQ', and 'PPz'. (The character set is all characters greater than or equal to 'A', and is case-sensitive.) A statement that does exactly what I want is "UPDATE item SET hasChildren = EXISTS (S