Fix for BUG#7793 "mysqlbinlog produces incorrect queries":

when printing SET @var in mysqlbinlog, backtick the collation (as BINARY is a reserved word)

mysql-test/r/ctype_ucs.result

@@ -520,7 +520,7 @@ Log_name	Pos	Event_type	Server_id	Orig_log_pos	Info
 master-bin.000001	79	User var	1	79	@`v`=_ucs2 0x006100620063 COLLATE ucs2_general_ci
 master-bin.000001	119	Query	1	119	use `test`; insert into t2 values (@v)
 /*!40019 SET @@session.max_insert_delayed_threads=0*/;
-SET @`v`:=_ucs2 0x006100620063 COLLATE ucs2_general_ci;
+SET @`v`:=_ucs2 0x006100620063 COLLATE `ucs2_general_ci`;
 use test;
 SET TIMESTAMP=10000;
 insert into t2 values (@v);

mysql-test/r/user_var.result

@@ -168,21 +168,24 @@ SET TIMESTAMP=10000;
 SET @`a b`='hello';
 INSERT INTO t1 VALUES(@`a b`);
 set @var1= "';aaa";
-insert into t1 values (@var1);
+SET @var2=char(ascii('a'));
+insert into t1 values (@var1),(@var2);
 show binlog events from 79;
 Log_name	Pos	Event_type	Server_id	Orig_log_pos	Info
 master-bin.000001	79	User var	1	79	@`a b`=_latin1 0x68656C6C6F COLLATE latin1_swedish_ci
 master-bin.000001	120	Query	1	120	use `test`; INSERT INTO t1 VALUES(@`a b`)
 master-bin.000001	184	User var	1	184	@`var1`=_latin1 0x273B616161 COLLATE latin1_swedish_ci
-master-bin.000001	226	Query	1	226	use `test`; insert into t1 values (@var1)
+master-bin.000001	226	User var	1	226	@`var2`=_binary 0x61 COLLATE binary
+master-bin.000001	264	Query	1	264	use `test`; insert into t1 values (@var1),(@var2)
 /*!40019 SET @@session.max_insert_delayed_threads=0*/;
-SET @`a b`:=_latin1 0x68656C6C6F COLLATE latin1_swedish_ci;
+SET @`a b`:=_latin1 0x68656C6C6F COLLATE `latin1_swedish_ci`;
 use test;
 SET TIMESTAMP=10000;
 INSERT INTO t1 VALUES(@`a b`);
-SET @`var1`:=_latin1 0x273B616161 COLLATE latin1_swedish_ci;
+SET @`var1`:=_latin1 0x273B616161 COLLATE `latin1_swedish_ci`;
+SET @`var2`:=_binary 0x61 COLLATE `binary`;
 SET TIMESTAMP=10000;
-insert into t1 values (@var1);
+insert into t1 values (@var1),(@var2);
 drop table t1;
 set @var= NULL ;
 select FIELD( @var,'1it','Hit') as my_column;

mysql-test/t/user_var.test

@@ -107,7 +107,8 @@ SET TIMESTAMP=10000;
 SET @`a b`='hello';
 INSERT INTO t1 VALUES(@`a b`);
 set @var1= "';aaa";
-insert into t1 values (@var1);
+SET @var2=char(ascii('a'));
+insert into t1 values (@var1),(@var2);
 show binlog events from 79;
 # more important than SHOW BINLOG EVENTS, mysqlbinlog (where we
 # absolutely need variables names to be quoted and strings to be

sql/log_event.cc

@@ -2459,7 +2459,7 @@ void User_var_log_event::print(FILE* file, bool short_form, char* last_db)
         */
         fprintf(file, ":=???;\n");
       else
-        fprintf(file, ":=_%s %s COLLATE %s;\n", cs->csname, hex_str, cs->name);
+        fprintf(file, ":=_%s %s COLLATE `%s`;\n", cs->csname, hex_str, cs->name);
       my_afree(hex_str);
     }
       break;