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[hotfix][doc] no space affect reading buffer doc (#3739)

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Backport of #3738 .
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谢磊 2018-12-04 03:38:27 +08:00 committed by Ivan Blinkov
parent 9805c4ae39
commit d84df9c283
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docs/en/operations/table_engines/buffer.md
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@ -6,9 +6,9 @@ Buffers the data to write in RAM, periodically flushing it to another table. Dur
Buffer(database, table, num_layers, min_time, max_time, min_rows, max_rows, min_bytes, max_bytes)
```
Engine parameters:database, table – The table to flush data to. Instead of the database name, you can use a constant expression that returns a string. num_layers – Parallelism layer. Physically, the table will be represented as 'num_layers' of independent buffers. Recommended value: 16.min_time, max_time, min_rows, max_rows, min_bytes, and max_bytes are conditions for flushing data from the buffer.
Engine parameters:database, table – The table to flush data to. Instead of the database name, you can use a constant expression that returns a string. num_layers – Parallelism layer. Physically, the table will be represented as 'num_layers' of independent buffers. Recommended value: 16. min_time, max_time, min_rows, max_rows, min_bytes, and max_bytes are conditions for flushing data from the buffer.
Data is flushed from the buffer and written to the destination table if all the 'min' conditions or at least one 'max' condition are met.min_time, max_time – Condition for the time in seconds from the moment of the first write to the buffer.min_rows, max_rows – Condition for the number of rows in the buffer.min_bytes, max_bytes – Condition for the number of bytes in the buffer.
Data is flushed from the buffer and written to the destination table if all the 'min' conditions or at least one 'max' condition are met.min_time, max_time – Condition for the time in seconds from the moment of the first write to the buffer. min_rows, max_rows – Condition for the number of rows in the buffer. min_bytes, max_bytes – Condition for the number of bytes in the buffer.
During the write operation, data is inserted to a 'num_layers' number of random buffers. Or, if the data part to insert is large enough (greater than 'max_rows' or 'max_bytes'), it is written directly to the destination table, omitting the buffer.