schema_of_json function
Applies to:  Databricks SQL 
 Databricks Runtime
Returns the schema of a JSON string in DDL format.
Syntax
schema_of_json(jsonStr [, options] )
Arguments
- jsonStr: A- STRINGexpression with a- JSONstring.
- options: An optional- MAPliterals with keys and values being- STRING.
Returns
A STRING holding a definition of an array of structs with n fields of strings where the column names are derived from the JSON keys.
The field values hold the derived formatted SQL types.
For details on options, see from_json function.
To derive the aggregated schema of a group of JSON strings use the schema_of_json_agg aggregate function.
Examples
SQL
> SELECT schema_of_json('[{"col":0}]');
 ARRAY<STRUCT<`col`: BIGINT>>
> SELECT schema_of_json('[{"col":01}]', map('allowNumericLeadingZeros', 'true'));
 ARRAY<STRUCT<`col`: BIGINT>>