sql语句与fmdb数据库记录

//创建数据

NSArray *arrname=@[@"sufei",@"tom",@"kimi",@"peter"];

NSArray *arrage=@[@"190",@"140",@"329",@"344"];

NSArray *arrgender=@[@"m",@"m",@"f",@"m"];

NSArray *arr=@[@"1000",@"1001",@"1002",@"1003"];

NSString *doc=[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];

NSString *fileName=[doc stringByAppendingPathComponent:@"teacher.db"];

FMDatabase *fmdb=[FMDatabase databaseWithPath:fileName];

//打开数据库建表

if ([fmdb open]) {

BOOL result=[fmdb executeUpdate:@"create table if not exists teacher (id integer PRIMARY KEY AUTOINCREMENT,name text,gender text,age integer)"];

if (result) {

NSLog(@"success");

}

else

{

NSLog(@"fail");

}

}

//添加列 不进行删除的话每次运行会报，添加重复列名的错。添加成绩列表

[fmdb executeUpdate:@"alter table teacher add chengji integer"];

//插入数据

for (int i=0; i<4; i++) {

[fmdb executeUpdate:@"INSERT INTO teacher(name,gender ,age ,chengji) VALUES (?,?,?,?);",arrname[i],arrgender[i],arrage[i],arr[i]];

}

//修改数据 当年龄为190的。修改成年龄为140

[fmdb executeUpdate:@"update teacher set age ='140' where age ='190'"];

//删除数据了一行

// [fmdb executeUpdate:@"delete from teacher where age='344'"];

//删除表添加的那一列

// [fmdb executeUpdate:@"alter table teacher drop column chengji"];

//改变表中列的数据类型

//alter table 表名 alter column 列名 列名的新数据类型

// 1.执行查询语句

FMResultSet *resultSet = [fmdb executeQuery:@"SELECT * FROM teacher"];

// 2.遍历结果

while ([resultSet next]) {

int ID = [resultSet intForColumn:@"id"];

NSString *name = [resultSet stringForColumn:@"name"];

int age = [resultSet intForColumn:@"age"];

NSString *gender=[resultSet stringForColumn:@"gender"];

int chengji = [resultSet intForColumn:@"chengji"];

NSLog(@"id=%d 名字：%@ 年龄：%d 性别：%@ 成绩:%d分", ID, name, age,gender,chengji);

}

//删除整个表

[fmdb executeUpdate:@"drop table teacher"];