remove duplicate type definition in function context
remove unused method in function context
not need stale state in vexpr context because vexpr is stateless and function context saves state and they are cloned.
remove useless slot_size in all tuple or slot descriptor.
remove doris_udf namespace, it is useless.
remove some unused macro definitions.
init v_conjuncts in vscanner, not need write the same code in every scanner.
using unique ptr to manage function context since it could only belong to a single expr context.
Issue Number: close #xxx
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Co-authored-by: yiguolei <yiguolei@gmail.com>
add a defer in fold constant to close.
add more type when call _get_result function in fold constant.3.
fix in can't handle null. eg:select 1 in (2, NULL, 1);
in java udf jni_ctx will be nullptr, so call close will be core dump.
Describe your changes.
