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clickhouseUsing ARRAY JOIN in queries


SELECT ts, list FROM tbl3 ARRAY JOIN listctrl + c
ts

datetime column

list

name of the array column to expand

tbl3

table with array column in it

ARRAY JOIN

will duplicate each row for each element of array and return resulting flat table


Usage example

SELECT * FROM tbl3;
SELECT ts, list FROM tbl3 ARRAY JOIN list
output
┌──────────────────ts─┬─list──────────┐
│ 2022-01-14 17:41:32 │ ['a','b','c'] │
│ 2022-01-14 17:41:38 │ ['b','c','d'] │
└─────────────────────┴───────────────┘

┌──────────────────ts─┬─list─┐
│ 2022-01-14 17:41:32 │ a    │
│ 2022-01-14 17:41:32 │ b    │
│ 2022-01-14 17:41:32 │ c    │
│ 2022-01-14 17:41:38 │ b    │
│ 2022-01-14 17:41:38 │ c    │
│ 2022-01-14 17:41:38 │ d    │
└─────────────────────┴──────┘