DynamicSchemaData

Decoded payload of an endpoint that returns a dynamic schema, such as execute_sql or aggregate_group_by.

Always present on the responses that declare it: the client decodes the payload on every such response before handing it back, so consumers never need to guard the field.

A statement that returns no result set — DDL such as CREATE TABLE … AS SELECT — still carries the field, but with no columns: read count_affected for those rather than column_headers.

The values are column-major, not a list of records: column_1 holds every value for the column named by column_headers[0], column_2 for column_headers[1], and so on.