Re: [Tarantool-patches] [PATCH v3 00/20] sql: prepared statements

[Kirill Yukhin <kyukhin@tarantool.org>]

Hello,

On 20 дек 15:47, Nikita Pettik wrote:
> Branch: https://github.com/tarantool/tarantool/tree/np/gh-2592-prepared-statements-v3
> Issue: https://github.com/tarantool/tarantool/issues/2592
> 
> V1: https://lists.tarantool.org/pipermail/tarantool-patches/2019-November/012274.html
> V2: https://lists.tarantool.org/pipermail/tarantool-patches/2019-November/012496.html
> 
> Changes in V3 (requested by server team):
> 
>  - Now there's no eviction policy, so statements reside in 'cache'
>    until explicit deallocation via 'unprepare' call or session's
>    disconect;
>  - instead of string ids, now we use numeric ids which correspond
>    to value of hash function applied to the string containing original
>    SQL request;
>  - in accordance with previous point, 'unprepare' support has been returned;
>  - since there's no eviction policy, disconnect event may turn out to
>    be expensive (in terms of deallocating all related to the session
>    prepared statements). To remove possible spikes in workload, we
>    maintain GC queue and reference counters for prepared statements.
>    When all sessions (previously refed statement) unref it, statement
>    gets into GC queue. In case of prepared statements holder is out
>    of memory, GC process is launched: all statements in queue are
>    deallocated;
>  - to track available in scope of session prepared statements, we
>    also maintain session-local map containing statement's IDs
>    allocated in this session.
> 
> Nikita Pettik (20):
>   sql: remove sql_prepare_v2()
>   sql: refactor sql_prepare() and sqlPrepare()
>   sql: move sql_prepare() declaration to box/execute.h
>   sql: rename sqlPrepare() to sql_stmt_compile()
>   sql: rename sql_finalize() to sql_stmt_finalize()
>   sql: rename sql_reset() to sql_stmt_reset()
>   sql: move sql_stmt_finalize() to execute.h
>   port: increase padding of struct port
>   port: add result set format and request type to port_sql
>   sql: resurrect sql_bind_parameter_count() function
>   sql: resurrect sql_bind_parameter_name()
>   sql: add sql_stmt_schema_version()
>   sql: introduce sql_stmt_sizeof() function
>   box: increment schema_version on ddl operations
>   sql: introduce sql_stmt_query_str() method
>   sql: move sql_stmt_busy() declaration to box/execute.h
>   sql: introduce holder for prepared statemets
>   box: introduce prepared statements
>   netbox: introduce prepared statements
>   sql: add cache statistics to box.info

I've checked your patchset into master.

--
Regards, Kirill Yukhin