1. 假設我們在hive中有兩張表，其中一張表是存使用者基本資訊，另一張表是存使用者的地址資訊等，表資料假設如下：

user_basic_info:

建表:

create table user_basic_info(id string, name string);
create table user_address(name string, address string);

load data local inpath '/home/jthink/work/workspace/hive/row_col_tran/data1' into table user_basic_info;
load data local inpath '/home/jthink/work/workspace/hive/row_col_tran/data2' into table user_address;
 

select max(ubi.id), ubi.name, concat_ws(',', collect_set(ua.address)) as address from user_basic_info ubi join user_address ua on ubi.name=ua.name group by ubi.name;

1       a       add1,add2
2       b       add3
3       c       add4
4       d       add5

2. 假設我們有一張表：

user_info:

select explode(address) as address from user_info;

這樣執行的結果只有address， 但是我們需要完整的資訊：

select id, name, explode(address) as address from user_info;

這樣做是不對的， UDTF's are not supported outside the SELECT clause, nor nested in expressions

所以我們需要這樣做：

select id, name, add from user_info ui lateral view explode(ui.address) adtable as add;

結果為：

1       a       add1
1       a       add2
2       b       add3
3       c       add4
4       d       add5