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homework/dmedvedev/clickhouse/8.CH_compretion.sql
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### **Задача 1.**
У тебя таблица `logs`с длинными строками — сообщения занимают много места.
| id | level | message | created_at |
| --- | --- | --- | --- |
| 1 | INFO | "User logged in" | 2024-07-01 10:00:00 |
| 2 | WARN | "Request took too long" | 2024-07-01 10:05:00 |
| 3 | ERROR | "Unable to connect to server" | 2024-07-01 10:10:00 |
1. Создай таблицу `logs` с колонкой `message CODEC(ZSTD(3))`.
2. Добавь `created_at CODEC(Delta, ZSTD)` — это улучшит хранение по времени.
3. Посмотри статистику сжатия:
SELECT
column,
codec_expression,
compression_codec
FROM system.columns
WHERE table = 'logs';
ОТВЕТ:
name type compression_codec
id UInt64 -
LEVEL String -
message String CODEC(ZSTD(3))
created_at DateTime CODEC(Delta(4), ZSTD(1))