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Update docs, make better

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avogar 2024-08-13 19:19:02 +00:00
parent 3cfb921bef
commit 70708fd5dc
3 changed files with 4 additions and 12 deletions
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7
docs/en/interfaces/schema-inference.md
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@ -1385,7 +1385,7 @@ DESC format(JSONEachRow, '{"id" : 1, "age" : 25, "name" : "Josh", "status" : nul
#### schema_inference_make_columns_nullable
Controls making inferred types `Nullable` in schema inference for formats without information about nullability.
If the setting is enabled, all inferred type will be `Nullable`, if disabled, the inferred type will be `Nullable` only if `input_format_null_as_default` is disabled and the column contains `NULL` in a sample that is parsed during schema inference.
If the setting is enabled, all inferred type will be `Nullable`, if disabled, the inferred type will never be `Nullable`, if set to `auto`, the inferred type will be `Nullable` only if the column contains `NULL` in a sample that is parsed during schema inference or file metadata contains information about column nullability.
Enabled by default.
@ -1408,15 +1408,13 @@ DESC format(JSONEachRow, $$
└─────────┴─────────────────────────┴──────────────┴────────────────────┴─────────┴──────────────────┴────────────────┘
```
```sql
SET schema_inference_make_columns_nullable = 0;
SET input_format_null_as_default = 0;
SET schema_inference_make_columns_nullable = 'auto';
DESC format(JSONEachRow, $$
{"id" : 1, "age" : 25, "name" : "Josh", "status" : null, "hobbies" : ["football", "cooking"]}
{"id" : 2, "age" : 19, "name" : "Alan", "status" : "married", "hobbies" : ["tennis", "art"]}
$$)
```
```response
┌─name────┬─type─────────────┬─default_type─┬─default_expression─┬─comment─┬─codec_expression─┬─ttl_expression─┐
│ id │ Int64 │ │ │ │ │ │
│ age │ Int64 │ │ │ │ │ │
@ -1428,7 +1426,6 @@ DESC format(JSONEachRow, $$
```sql
SET schema_inference_make_columns_nullable = 0;
SET input_format_null_as_default = 1;
DESC format(JSONEachRow, $$
{"id" : 1, "age" : 25, "name" : "Josh", "status" : null, "hobbies" : ["football", "cooking"]}
{"id" : 2, "age" : 19, "name" : "Alan", "status" : "married", "hobbies" : ["tennis", "art"]}

4
docs/en/operations/settings/settings-formats.md
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@ -171,8 +171,8 @@ If the `schema_inference_hints` is not formated properly, or if there is a typo
## schema_inference_make_columns_nullable {#schema_inference_make_columns_nullable}
Controls making inferred types `Nullable` in schema inference for formats without information about nullability.
If the setting is enabled, the inferred type will be `Nullable` only if column contains `NULL` in a sample that is parsed during schema inference.
Controls making inferred types `Nullable` in schema inference.
If the setting is enabled, all inferred type will be `Nullable`, if disabled, the inferred type will never be `Nullable`, if set to `auto`, the inferred type will be `Nullable` only if the column contains `NULL` in a sample that is parsed during schema inference or file metadata contains information about column nullability.
Default value: `true`.

5
src/Processors/Formats/ISchemaReader.cpp
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@ -56,11 +56,6 @@ void checkFinalInferredType(
if (settings.schema_inference_make_columns_nullable == 1)
type = makeNullableRecursively(type);
/// In case when data for some column could contain nulls and regular values,
/// resulting inferred type is Nullable.
/// If input_format_null_as_default is enabled, we should remove Nullable type.
else if (settings.null_as_default)
type = removeNullable(type);
}
void ISchemaReader::transformTypesIfNeeded(DB::DataTypePtr & type, DB::DataTypePtr & new_type)