On 5/2/07, Tito Ciuro <[EMAIL PROTECTED]> wrote:
Hello,Assume the following scenario: I store people in a table, like this: People ROWID, idx GUID, idx First, idx Last, idx Email ... In the app, the user can select People GUIDs from different sources and then retrieve the info from the database. The easy/suboptimal route to retrieve the records would be to perform a SELECT per GUID selected. I thought of something like this: SELECT * FROM People where GUID in ("ABC", "RDT", "TUV"); Is there a better way to include all these GUIDs on a single SQL statement to speed things up?
When you say "speed things up," is it not fast enough yet? Numbers would be helpful.
Questions I have: 1) Is this the best way to solve the problem? Suggestions?
unless you change your attribution (for example, tag your data by GUID-types, if there is such a thing in your case), the above is the best way, perhaps the only way. Internally, I believe the IN clause gets converted to a set of OR matches as in GUID = 'ABC' OR GUID = 'XYZ' OR... (or is it the other way around?)
2) Is there a limit on the number of parameters I can pass to "in"?
dunno... try it.
What if I have, say, 500 to retrieve? Will SQLite complain about this?
try it, if SQLite complains, you will know, and you will have to approach the problem differently ;-)
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