我的数据如下:
USERNAME ENTRY_TYPE ENTRY_CHOICE
user_a ice_cream lemon
user_b ice_cream strawberry
user_b ice_cream blueberry
user_c ice_cream chocolate
user_c ice_cream salt
user_c ice_cream powerpuff
鉴于冰淇淋的选择范围是一到三种,我怎样才能将数据集放入每个用户的一行中?
USERNAME OTHER_DATA ICE_CREAM_CHOICE_1 ICE_CREAM_CHOICE_2 ICE_CREAM_CHOICE_3
user_a [...] lemon
user_b [...] strawberry blueberry
user_c [...] chocolate salt powerpuff