I have a TEXT column and I want to match all rows where the value has a certain prefix. For example,
WHERE mycol LIKE 'myprefix%' However, I noticed in some optimization guidelines that this will not use the index and instead you should do this: WHERE mycol >= 'myprefix' AND mycol < 'myprefiy' Instead of simple A-Z chars, I have a whole variety of UTF-8 chars (think chinese characters). My question is, how to work out the next char in UTF-8? Is it enough to add one to the codepoint, such as: String lowerBound = "myprefix"; int codepoint = Character.codePointAt(lowerBound, lowerBound.length() - 1); String upperBound = lowerBound.substring(0, lowerBound.length() - 1) + Character.toChars(codePoint + 1); String sql = "SELECT * FROM mytable WHERE mycol >= '" + lowerBound + '" AND mycol < '" + upperBoundPrefix + "'" ? --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Android Developers" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~----------~----~----~----~------~----~------~--~---
