sqlite fetch statement - objective-c

Question

Good day,
I need to fetch rows from my sqlite table, but I need to pass multiple parameters. This is my statement that does not work.
SELECT * FROM messages WHERE currentuser=\"%#\" AND (belongstouser=\"%#\" OR mymsgforuser=\"%#\") ORDER BY ID ASC
I need it to first check for the currentuser match, then out of those matches to check for either the belongstouser or mymsgforuser matches. Is it possible to nest a sqlite statement in this fashion? I tried removing the parenthesis and that didn't work either. I also searched the sqlite documentation and could not find a solution.

Answer 1

I can see wrong SQL syntax. string constants must be quoted with single quotes (') instead of (")
And as rmaddy said, you'd better avoid stringWithFormat. Use prepare statement technique.
- (BOOL)_prepareStatement:(sqlite3_stmt **)statement withSQL:(const char *)sql {
sqlite3_stmt *s = *statement;
//caDatabase is declared as sqlite3 *caDatabase object
if (nil == s && sqlite3_prepare_v2(caDatabase, sql, -1, &s, NULL)!= SQLITE_OK)
{
[self _showError];
*statement = nil;
return NO;
}
*statement = s;
return YES;
}
- (caObjectId)existObject:(caObjectId)objId withType:(caCacheObjectType)objType libraryID:(int)aLibraryID
{
#synchronized (self)
{
const char *caSQLexistObj = "SELECT id FROM objects WHERE objId = ? AND objType = ? AND libraryID = ?";
if(![self _prepareStatement:&ca_existObjectStatement withSQL:caSQLexistObj]) {
//produce some error message
return;
}
sqlite3_bind_int(ca_existObjectStatement, 1, objId);
sqlite3_bind_int(ca_existObjectStatement, 2, objType);
sqlite3_bind_int(ca_existObjectStatement, 3, aLibraryID);
NSInteger result = sqlite3_step(ca_existObjectStatement);
if (result != SQLITE_ROW)
{
sqlite3_reset(ca_existObjectStatement);
return caObjectIdNone;
}
caObjectId cacheId = sqlite3_column_int(ca_existObjectStatement, 0);
sqlite3_reset(ca_existObjectStatement);
return cacheId;
}
}