Add ability to force alternative upsert implementation in mysql

src/ejabberd_option.erl

@@ -143,6 +143,7 @@
 -export([sm_use_cache/0, sm_use_cache/1]).
 -export([sql_connect_timeout/0, sql_connect_timeout/1]).
 -export([sql_database/0, sql_database/1]).
+-export([sql_flags/0, sql_flags/1]).
 -export([sql_keepalive_interval/0, sql_keepalive_interval/1]).
 -export([sql_odbc_driver/0, sql_odbc_driver/1]).
 -export([sql_password/0, sql_password/1]).
@@ -964,6 +965,13 @@ sql_database() ->
 sql_database(Host) ->
     ejabberd_config:get_option({sql_database, Host}).
 
+-spec sql_flags() -> ['mysql_alternative_upsert'].
+sql_flags() ->
+    sql_flags(global).
+-spec sql_flags(global | binary()) -> ['mysql_alternative_upsert'].
+sql_flags(Host) ->
+    ejabberd_config:get_option({sql_flags, Host}).
+
 -spec sql_keepalive_interval() -> 'undefined' | pos_integer().
 sql_keepalive_interval() ->
     sql_keepalive_interval(global).

src/ejabberd_options.erl

@@ -424,6 +424,8 @@ opt_type(sql_username) ->
     econf:binary();
 opt_type(sql_prepared_statements) ->
     econf:bool();
+opt_type(sql_flags) ->
+    econf:list_or_single(econf:enum([mysql_alternative_upsert]), [sorted, unique]);
 opt_type(trusted_proxies) ->
     econf:either(all, econf:list(econf:ip_mask()));
 opt_type(use_cache) ->
@@ -708,6 +710,7 @@ options() ->
      {sql_start_interval, timer:seconds(30)},
      {sql_username, <<"ejabberd">>},
      {sql_prepared_statements, true},
+     {sql_flags, []},
      {trusted_proxies, []},
      {validate_stream, false},
      {websocket_origin, []},

src/ejabberd_sql.erl

@@ -1148,7 +1148,11 @@ get_db_version(#state{db_type = pgsql} = State) ->
             ?WARNING_MSG("Error getting pgsql version: ~p", [Res]),
             State
     end;
-get_db_version(#state{db_type = mysql} = State) ->
+get_db_version(#state{db_type = mysql, host = Host} = State) ->
+    DefaultUpsert = case lists:member(mysql_alternative_upsert, ejabberd_option:sql_flags(Host)) of
+			true -> 1;
+			_ -> 0
+		    end,
     case mysql_to_odbc(p1_mysql_conn:squery(State#state.db_ref,
 					    [<<"select version();">>], self(),
 					    [{timeout, 5000},
@@ -1160,10 +1164,10 @@ get_db_version(#state{db_type = mysql} = State) ->
 		    V = ((bin_to_int(V1)*1000)+bin_to_int(V2))*1000+bin_to_int(V3),
 		    TypeA = binary_to_atom(Type, utf8),
 		    Flags = case TypeA of
-				'MariaDB' -> 0;
+				'MariaDB' -> DefaultUpsert;
 				_ when V >= 5007026 andalso V < 8000000 -> 1;
 				_ when V >= 8000020 -> 1;
-				_ -> 0
+				_ -> DefaultUpsert
 			    end,
 		    State#state{db_version = {V, TypeA, Flags}};
 		{match, [V1, V2, V3]} ->
@@ -1171,7 +1175,7 @@ get_db_version(#state{db_type = mysql} = State) ->
 		    Flags = case V of
 				_ when V >= 5007026 andalso V < 8000000 -> 1;
 				_ when V >= 8000020 -> 1;
-				_ -> 0
+				_ -> DefaultUpsert
 			    end,
 		    State#state{db_version = {V, unknown, Flags}};
 		_ ->