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JSONColumns

InputOutputAlias

Description

Tip

The output of the JSONColumns* formats provides the ClickHouse field name and then the content of each row in the table for that field; visually, the data is rotated 90 degrees to the left.

In this format, all data is represented as a single JSON Object.

Note

The JSONColumns format buffers all data in memory and then outputs it as a single block, so, it can lead to high memory consumption.

Example Usage

Example:

{
"num": [42, 43, 44],
"str": ["hello", "hello", "hello"],
"arr": [[0,1], [0,1,2], [0,1,2,3]]
}

Format Settings

During import, columns with unknown names will be skipped if setting input_format_skip_unknown_fields is set to 1. Columns that are not present in the block will be filled with default values (you can use the input_format_defaults_for_omitted_fields setting here)