IOS Study Notes (16)-Database Operations (using FMDB)

FMDB (https://github.com/ccgus/fmdb

FMResultSet: Execute to query an FMDatabase result set, which is similar to the android Cursor.
FMDatabaseQueue: this class is used when multiple threads are used to execute queries and updates.

 

db = [FMDatabase databaseWithPath:database_path];

 

.

 

[db open]

Return BOOL type.

 

 

[db close]

 

 

 

if ([db open]) {        NSString *sqlCreateTable =  [NSString stringWithFormat:@"CREATE TABLE IF NOT EXISTS '%@' ('%@' INTEGER PRIMARY KEY AUTOINCREMENT, '%@' TEXT, '%@' INTEGER, '%@' TEXT)",TABLENAME,ID,NAME,AGE,ADDRESS];        BOOL res = [db executeUpdate:sqlCreateTable];        if (!res) {            NSLog(@"error when creating db table");        } else {            NSLog(@"success to creating db table");        }        [db close];    }

 

 

If ([db open]) {NSString * insertSql1 = [NSString stringWithFormat: @ "insert into '% @' ('% @', '% @', '% @') VALUES ('% @', '% @', '% @') ", TABLENAME, NAME, AGE, ADDRESS, @" Zhang San ", @" 13 ", @ "Jinan"]; BOOL res = [db executeUpdate: insertSql1]; NSString * insertSql2 = [NSString stringWithFormat: @ "insert into '% @' ('% @', '% @', '% @') VALUES ('% @', '% @', '% @') ", TABLENAME, NAME, AGE, ADDRESS, @ "Li Si", @ "12", @ "Jinan"]; BOO L res2 = [db executeUpdate: insertSql2]; if (! Res) {NSLog (@ "error when insert db table");} else {NSLog (@ "success to insert db table");} [db close];}

 

 

if ([db open]) {        NSString *updateSql = [NSString stringWithFormat:                               @"UPDATE '%@' SET '%@' = '%@' WHERE '%@' = '%@'",                               TABLENAME,   AGE,  @"15" ,AGE,  @"13"];        BOOL res = [db executeUpdate:updateSql];        if (!res) {            NSLog(@"error when update db table");        } else {            NSLog(@"success to update db table");        }        [db close];    }

 

 

If ([db open]) {NSString * deleteSql = [NSString stringWithFormat: @ "delete from % @ where % @ = '% @'", TABLENAME, NAME, @ "James"]; BOOL res = [db executeUpdate: deleteSql]; if (! Res) {NSLog (@ "error when delete db table");} else {NSLog (@ "success to delete db table");} [db close];}

 

 

if ([db open]) {        NSString * sql = [NSString stringWithFormat:                          @"SELECT * FROM %@",TABLENAME];        FMResultSet * rs = [db executeQuery:sql];        while ([rs next]) {            int Id = [rs intForColumn:ID];            NSString * name = [rs stringForColumn:NAME];            NSString * age = [rs stringForColumn:AGE];            NSString * address = [rs stringForColumn:ADDRESS];            NSLog(@"id = %d, name = %@, age = %@  address = %@", Id, name, age, address);        }        [db close];    }

 

 

FMDatabaseQueue * queue = [FMDatabaseQueue queue: database_path]; q1 = dispatch_queue_create ("queue1", NULL); q2 = partition ("queue2", NULL); dispatch_async (q1, ^ {for (int I = 0; I <50; ++ I) {[queue inDatabase: ^ (FMDatabase * db2) {NSString * insertSql1 = [NSString stringWithFormat: @ "insert into '% @' ('% @', '% @', '% @') VALUES (?, ?, ?) ", TABLENAME, NAME, AGE, ADDRESS]; NSString * name = [NSString stringWithFormat: @" jack % d ", I]; NSString * age = [NSString stringWithFormat: @ "% d", 10 + I]; BOOL res = [db2 executeUpdate: insertSql1, name, age, @ "Jinan"]; if (! Res) {NSLog (@ "error to inster data: % @", name);} else {NSLog (@ "succ to inster data: % @", name) ;}}] ;}}); dispatch_async (q2, ^ {for (int I = 0; I <50; ++ I) {[queue inDatabase: ^ (FMDatabase * db2) {NSString * insertSql2 = [NSString stringWithFormat: @ "insert into '% @' ('% @', '% @', '% @') VALUES (?, ?, ?) ", TABLENAME, NAME, AGE, ADDRESS]; NSString * name = [NSString stringWithFormat: @" lilei % d ", I]; NSString * age = [NSString stringWithFormat: @ "% d", 10 + I]; BOOL res = [db2 executeUpdate: insertSql2, name, age, @ "Beijing"]; if (! Res) {NSLog (@ "error to inster data: % @", name);} else {NSLog (@ "succ to inster data: % @", name) ;}}] ;}});

 

@ Zhang xingye TBOW(#-> @)

 

 

 

 

Https://github.com/ccgus/fmdb