query_options object cannot be changed after it was created. For
internal uses, like internal query paging, it is needed to create a new
object based on some of the data from an existing one with a new paging
state.
This patch adds a constructor from a unique_ptr and paging state.
using unique_ptr behave similar to move modify constructor.
Signed-off-by: Amnon Heiman <amnon@scylladb.com>
Currently, the code is using bytes_opt and bytes_view_opt to represent
CQL values, which can hold a value or null. In preparation for
supporting a third state, unset value introduced in CQL v4, introduce
new raw_value and raw_value_view types and use them instead.
The new types are based on boost::variant<> and are capable of holding
null, unset values, and blobs that represent a value.
query_options::prepare() changes the values array, but this is not the
one used by query_options internally (e.g., in get_value_at). So we
need to also recalculate the value_views after prepare() is called.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
Having both the values and value_views arguments in the query_options
ctor is confusing, since query_options uses only the value_views field
but that is not communicated to the caller.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
Store values as bytes view when possible. This improves the CQL protocol
option parsing path by avoiding allocating memory and copying individual
values as "bytes" objects.
Please note that we retain the non-view version for internal queries
where performance is not as important.
Signed-off-by: Pekka Enberg <penberg@cloudius-systems.com>
query_options is needlessy organized as a class hierarchy, even though it's
really a simple value type.
Fix by folding all the derived classes into it.
