--- slug: /en/operations/system-tables/schema_inference_cache --- # schema_inference_cache Contains information about all cached file schemas. Columns: - `storage` ([String](/docs/en/sql-reference/data-types/string.md)) — Storage name: File, URL, S3 or HDFS. - `source` ([String](/docs/en/sql-reference/data-types/string.md)) — File source. - `format` ([String](/docs/en/sql-reference/data-types/string.md)) — Format name. - `additional_format_info` ([String](/docs/en/sql-reference/data-types/string.md)) - Additional information required to identify the schema. For example, format specific settings. - `registration_time` ([DateTime](/docs/en/sql-reference/data-types/datetime.md)) — Timestamp when schema was added in cache. - `schema` ([String](/docs/en/sql-reference/data-types/string.md)) - Cached schema. **Example** Let's say we have a file `data.jsonl` with this content: ```json {"id" : 1, "age" : 25, "name" : "Josh", "hobbies" : ["football", "cooking", "music"]} {"id" : 2, "age" : 19, "name" : "Alan", "hobbies" : ["tennis", "art"]} {"id" : 3, "age" : 32, "name" : "Lana", "hobbies" : ["fitness", "reading", "shopping"]} {"id" : 4, "age" : 47, "name" : "Brayan", "hobbies" : ["movies", "skydiving"]} ``` :::tip Place `data.jsonl` in the `user_files_path` directory. You can find this by looking in your ClickHouse configuration files. The default is: ``` <user_files_path>/var/lib/clickhouse/user_files/</user_files_path> ``` ::: Open `clickhouse-client` and run the `DESCRIBE` query: ```sql DESCRIBE file('data.jsonl') SETTINGS input_format_try_infer_integers=0; ``` ```response ┌─name────┬─type────────────────────┬─default_type─┬─default_expression─┬─comment─┬─codec_expression─┬─ttl_expression─┐ │ id │ Nullable(Float64) │ │ │ │ │ │ │ age │ Nullable(Float64) │ │ │ │ │ │ │ name │ Nullable(String) │ │ │ │ │ │ │ hobbies │ Array(Nullable(String)) │ │ │ │ │ │ └─────────┴─────────────────────────┴──────────────┴────────────────────┴─────────┴──────────────────┴────────────────┘ ``` Let's see the content of the `system.schema_inference_cache` table: ```sql SELECT * FROM system.schema_inference_cache FORMAT Vertical ``` ```response Row 1: ────── storage: File source: /home/droscigno/user_files/data.jsonl format: JSONEachRow additional_format_info: schema_inference_hints=, max_rows_to_read_for_schema_inference=25000, schema_inference_make_columns_nullable=true, try_infer_integers=false, try_infer_dates=true, try_infer_datetimes=true, try_infer_numbers_from_strings=true, read_bools_as_numbers=true, try_infer_objects=false registration_time: 2022-12-29 17:49:52 schema: id Nullable(Float64), age Nullable(Float64), name Nullable(String), hobbies Array(Nullable(String)) ``` **See also** - [Automatic schema inference from input data](/docs/en/interfaces/schema-inference.md)