MOD: add getAllItemIDsFromTable:tableName and test

YTKKeyValueStore/YTKKeyValueStore.h

@@ -51,6 +51,8 @@
 
 - (NSArray *)getAllItemsFromTable:(NSString *)tableName;
 
+- (NSArray *)getAllItemIDsFromTable:(NSString *)tableName;
+
 - (NSUInteger)getCountFromTable:(NSString *)tableName;
 
 - (void)deleteObjectById:(NSString *)objectId fromTable:(NSString *)tableName;

YTKKeyValueStore/YTKKeyValueStore.m

@@ -55,6 +55,8 @@ PRIMARY KEY(id)) \
 
 static NSString *const SELECT_ALL_SQL = @"SELECT * from %@";
 
+static NSString *const SELECT_ALL_ID_SQL = @"SELECT id from %@";
+
 static NSString *const COUNT_ALL_SQL = @"SELECT count(*) as num from %@";
 
 static NSString *const CLEAR_ALL_SQL = @"DELETE from %@";
@@ -288,6 +290,24 @@ - (NSArray *)getAllItemsFromTable:(NSString *)tableName {
     return result;
 }
 
+- (NSArray *)getAllItemIDsFromTable:(NSString *)tableName {
+    if ([YTKKeyValueStore checkTableName:tableName] == NO) {
+        return nil;
+    }
+    NSString * sql = [NSString stringWithFormat:SELECT_ALL_ID_SQL, tableName];
+    __block NSMutableArray * result = [NSMutableArray array];
+    [_dbQueue inDatabase:^(FMDatabase *db) {
+        FMResultSet * rs = [db executeQuery:sql];
+        while ([rs next]) {
+            YTKKeyValueItem * item = [[YTKKeyValueItem alloc] init];
+            item.itemId = [rs stringForColumn:@"id"];
+            [result addObject:item.itemId];
+        }
+        [rs close];
+    }];
+    return result;
+}
+
 - (NSUInteger)getCountFromTable:(NSString *)tableName
 {
     if ([YTKKeyValueStore checkTableName:tableName] == NO) {

YTKKeyValueStoreTests/YTKKeyValueStoreTests.m

@@ -70,6 +70,20 @@ - (void)testSaveNumber {
     XCTAssertNil(result);
 }
 
+- (void)testGetAllItemIDsFromTable {
+    NSNumber *number1 = @1;
+    NSString *key1 = @"key1";
+    NSNumber *number2 = @2;
+    NSString *key2 = @"key2";
+    NSArray *IDs = @[key1, key2];
+    [_store putNumber:number1 withId:key1 intoTable:_tableName];
+    [_store putNumber:number2 withId:key2 intoTable:_tableName];
+
+    NSArray *result;
+    result = [_store getAllItemIDsFromTable:_tableName];
+    XCTAssertEqualObjects(result, IDs);
+}
+
 - (void)testPerformanceExample {
     // This is an example of a performance test case.
     [self measureBlock:^{