FMDB 查询是否存在某个表,或某个数据

 //监测数据库中我要需要的表是否已经存在
NSString *existsSql = [NSString stringWithFormat:@"select count(name) as countNum from sqlite_master where type = 'table' and name = '%@'", @"Member" ];
FMResultSet *rs = [membersDB executeQuery:existsSql]; if ([rs next]) {
NSInteger count = [rs intForColumn:@"countNum"];
NSLog(@"The table count: %li", count);
if (count == 1) {
NSLog(@"存在");
return;
}
}
//检测某个数据是否存在
FMResultSet *rs =[membersDB executeQuery:@"SELECT COUNT(Name) AS countNum FROM Member WHERE Name = ?",self.nameTextField.text];
while ([rs next]) {
NSInteger count = [rs intForColumn:@"countNum"];
if (count > 0) {
//存在
}
else
{
//不存在
}
}
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