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Coordinator DB
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Load and export data ​

Data exchange has two parts: a format describes the bytes, and a table schema describes their SQL values. Create explicit target columns before importing rows.

Choose a direction ​

Formats can support input, output or both. Inspect their registered directions before choosing one:

sql
SELECT name, is_input, is_output
FROM system.formats
WHERE name IN ('csv', 'json_each_row', 'parquet', 'yaml')
ORDER BY name
FORMAT csv;
text
"csv",1,1
"json_each_row",1,1
"parquet",1,1
"yaml",1,1

Names use snake_case and ignore ASCII case. CamelCase names are not aliases.

Load rows ​

Native stdin, native FROM INFILE and HTTP attached input send data to INSERT FORMAT. FROM INFILE reads the client's files. file() instead reads confined regular files under the server's user_files_path and can be used in SELECT or INSERT SELECT.

Most file sources require an explicit column/type list. Only form and parquet_metadata can supply their own column metadata.

Export rows ​

Use SELECT FORMAT to choose a result encoding. Native --query writes exact bytes to stdout, including binary containers. Redirect binary output to a file rather than treating it as a terminal table.

Guides ​

The format reference defines layouts, settings and type mappings.