Delete data from sqlite3 based on time

Delete based on time

-(void) Deletedatawithtime: (NSString *) time at: (NSString *) tablename{

NSString *deletesql = @ "Delete from lbbmestable where Id =?";

NSString *tab = [TableName stringbyreplacingoccurrencesofstring:@ ". db" withstring:@ ""];

NSString *deletesql = [NSString stringwithformat:@ "Delete from%@ where time <?", Tab];

NSData *messagedata = [message datausingencoding:nsutf8stringencoding];

NSString *path = [Nshomedirectory () stringbyappendingstring:[nsstring stringwithformat:@ "/Documents/%@", TableName]] ;

_database = [Fmdatabase Databasewithpath:path];

if ([_database Open]) {

if (![ _database Executeupdate:deletesql,time]) {

NSLog (@ "Delete error:%@", _database.lasterrormessage);

}

}

[_database Close];

}

This allows the data to be deleted directly, where time is stored as a string, equivalent to the comparison string,

Calculate the distance now how many seconds, the return is the full string of time, such as 2014-01-04 06:06:06, if the incoming negative, it is the previous time

+ (NSString *) Timestrsincenow: (nstimeinterval) timeinterval{

nsdate* dat = [NSDate datewithtimeintervalsincenow:timeinterval];//calculates a time before so much time

NSDateFormatter *formatter=[[nsdateformatter alloc] init];

[Formatter setdateformat:@ "Yyyy-mm-dd HH:mm:ss"];

NSString *pasttime = [Formatter stringfromdate:dat];

return pasttime;

}

Delete data from sqlite3 based on time