Purpose
Retrieves the schema for a DATASET data type instance.
Syntax
void FNC_GetDatasetSchema ( DATASET_HANDLE datasetHandle, void* schemaBuf, int schemaBufLen, int* actualSchemaLength, dataset_schema_encoding_t schemaEncoding)
- DATASET_HANDLE datasetHandle
- A handle to a DATASET data type instance that is defined to be an input parameter to an external routine.
- void* schemaBuf
- Return parameter that contains the UNICODE characters in JSON format representing the schema.
- int schemaBufLen
- The length of the buffer used to store the schema, in bytes.
- int* actualSchemaLength
- Return parameter specifying the length of the schema for this DATASET data type instance, in bytes.
- dataset_schema_encoding_t schemaEncoding
- The encoding in which the user would like to retrieve the schema.
Usage Notes
FNC_GetDatasetSchema can be used to retrieve the schema of a DATASET data type, regardless of storage format or size. The schema is returned as UNICODE text, encoded in either UTF-8 or UTF-16, depending on the value of the schemaEncoding parameter.
Note that the schema is returned without any special formatting, in its JSON encoding and with UNICODE characters.
Use FNC_GetDatasetInfo to determine the appropriate buffer size that can store the schema. If the buffer passed into this routine is too small to contain the entire schema, an error is reported.
For best performance, Use FNC_GetDatasetSchema when the schema is not stored as a LOB. If FNC_GetDatasetInfo returns schemaLob = 0, you can use FNC_GetDatasetSchema; otherwise, you should use FNC_GetDatasetSchemaLob instead.