const static NSInteger FAMILY_LIST_DB_MANAGER_VER = 1;
@implementation KSFamilyListDBManager
{
DBManager *_dbMgr;
}
+ (instancetype)sharedManager
{
static KSFamilyListDBManager *s_instance = nil;
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
s_instance = [[KSFamilyListDBManager alloc] init];
});
return s_instance;
}
- (id)init {
self = [super init];
if (self) {
_dbMgr = [DBManager defaultMgr];
[self createTables];
// 升级操作
NSInteger ver = [[ConfigDBManager sharedManager] familyListDBManagerVersion];
if (ver < 1) {
[[ConfigDBManager sharedManager] setFamilyListDBManagerVersion:FAMILY_LIST_DB_MANAGER_VER];
} else if (ver < FAMILY_LIST_DB_MANAGER_VER) {
[self upgrade];
}
}
return self;
}
- (void)upgrade {
//获取存储好的原版本号
NSInteger oldVersionNum = [[ConfigDBManager sharedManager] familyListDBManagerVersion];
if (FAMILY_LIST_DB_MANAGER_VER <= oldVersionNum || oldVersionNum == 0) {
return;
}
//升级
[self upgrade:oldVersionNum];
// 保存新的版本号到库中 -这里大家可以使用NSUserDefault存储
[[ConfigDBManager sharedManager] setFamilyListDBManagerVersion:FAMILY_LIST_DB_MANAGER_VER];
}
- (void)upgrade:(NSInteger)oldVersion {
if (oldVersion >= FAMILY_LIST_DB_MANAGER_VER) {
return;
}
switch (oldVersion) {
case 0:
break;
case 1:
[self upgradeFrom1To2];
break;
case 2:
break;
default:
break;
}
oldVersion ++;
// 递归判断是否需要升级
[self upgrade:oldVersion];
}
- (void)upgradeFrom1To2 {
//这里执行Sql语句 执行版本1到版本2的更新
}
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