WL#1567: Add ROW_COUNT() Function to retrieve count of rows updated/inserted/deleted

mysql-test/r/sp.result:
  New test cases for function ROW_COUNT().
mysql-test/t/sp.test:
  New test cases for function ROW_COUNT().
sql/item_func.cc:
  New Item_func_row_count.
sql/item_func.h:
  New Item_func_row_count.
sql/lex.h:
  New symbol for function ROW_COUNT().
sql/sql_class.h:
  New slot in THD for storing the row_count after insert, delete and update.
sql/sql_delete.cc:
  Set thd->row_count_func when deleting.
sql/sql_insert.cc:
  Set thd->row_count_func when inserting.
sql/sql_parse.cc:
  Stored procedure CALLs send the row count from the last insert, delete or update.
sql/sql_update.cc:
  Set thd->row_count_func when updating.
sql/sql_yacc.yy:
  New function ROW_COUNT().

mysql-test/r/sp.result

@@ -802,6 +802,28 @@ use test|
 drop database sp_db3|
 select type,db,name from mysql.proc where db = 'sp_db3'|
 type	db	name
+create procedure rc()
+begin
+delete from t1;
+insert into t1 values ("a", 1), ("b", 2), ("c", 3);
+end|
+call rc()|
+select row_count()|
+row_count()
+3
+update t1 set data=42 where id = "b";
+select row_count()|
+row_count()
+1
+delete from t1|
+select row_count()|
+row_count()
+3
+delete from t1|
+select row_count()|
+row_count()
+0
+drop procedure rc|
 create procedure bug822(a_id char(16), a_data int)
 begin
 declare n int;

mysql-test/t/sp.test

@@ -931,6 +931,25 @@ drop database sp_db3|
 select type,db,name from mysql.proc where db = 'sp_db3'|
 
 
+# ROW_COUNT() function after a CALL
+# We test the other cases here too, although it's not strictly SP specific
+create procedure rc()
+begin
+  delete from t1;
+  insert into t1 values ("a", 1), ("b", 2), ("c", 3);
+end|
+
+call rc()|
+select row_count()|
+update t1 set data=42 where id = "b";
+select row_count()|
+delete from t1|
+select row_count()|
+delete from t1|
+select row_count()|
+drop procedure rc|
+
+
 #
 # Test cases for old bugs
 #

sql/item_func.cc

@@ -3206,6 +3206,15 @@ longlong Item_func_is_used_lock::val_int()
 }
 
 
+longlong Item_func_row_count::val_int()
+{
+  DBUG_ASSERT(fixed == 1);
+  THD *thd= current_thd;
+
+  return thd->row_count_func;
+}
+
+
 Item_func_sp::Item_func_sp(sp_name *name)
   :Item_func(), m_name(name), m_sp(NULL)
 {

sql/item_func.h

@@ -1076,6 +1076,16 @@ enum Cast_target
 };
 
 
+class Item_func_row_count :public Item_int_func
+{
+public:
+  Item_func_row_count() :Item_int_func() {}
+  longlong val_int();
+  const char *func_name() const { return "row_count"; }
+  void fix_length_and_dec() { decimals= 0; maybe_null=0; }
+};
+
+
 /*
  *
  * Stored FUNCTIONs

sql/lex.h

@@ -681,6 +681,7 @@ static SYMBOL sql_functions[] = {
   { "RELEASE_LOCK",	F_SYM(FUNC_ARG1),0,CREATE_FUNC(create_func_release_lock)},
   { "REVERSE",		F_SYM(FUNC_ARG1),0,CREATE_FUNC(create_func_reverse)},
   { "ROUND",		SYM(ROUND)},
+  { "ROW_COUNT",	SYM(ROW_COUNT_SYM)},
   { "RPAD",		F_SYM(FUNC_ARG3),0,CREATE_FUNC(create_func_rpad)},
   { "RTRIM",		F_SYM(FUNC_ARG1),0,CREATE_FUNC(create_func_rtrim)},
   { "SEC_TO_TIME",	F_SYM(FUNC_ARG1),0,CREATE_FUNC(create_func_sec_to_time)},

sql/sql_class.h

@@ -829,6 +829,7 @@ class THD :public ilink,
   bool	     charset_is_system_charset, charset_is_collation_connection;
   bool       slow_command;
 
+  ulong      row_count_func;	/* For the ROW_COUNT() function */
   sp_rcontext *spcont;		// SP runtime context
   sp_cache   *sp_proc_cache;
   sp_cache   *sp_func_cache;

sql/sql_delete.cc

@@ -96,6 +96,7 @@ int mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, SQL_LIST *order,
   {
     delete select;
     free_underlaid_joins(thd, &thd->lex->select_lex);
+    thd->row_count_func= 0;
     send_ok(thd,0L);
     DBUG_RETURN(0);				// Nothing to delete
   }
@@ -245,6 +246,7 @@ int mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds, SQL_LIST *order,
     send_error(thd,thd->killed_errno());
   else
   {
+    thd->row_count_func= deleted;
     send_ok(thd,deleted);
     DBUG_PRINT("info",("%d records deleted",deleted));
   }
@@ -550,7 +552,10 @@ bool multi_delete::send_eof()
   if (local_error)
     ::send_error(thd);
   else
+  {
+    thd->row_count_func= deleted;
     ::send_ok(thd, deleted);
+  }
   return 0;
 }
 

sql/sql_insert.cc

@@ -419,7 +419,10 @@ int mysql_insert(THD *thd,TABLE_LIST *table_list,
     goto abort;
   if (values_list.elements == 1 && (!(thd->options & OPTION_WARNINGS) ||
 				    !thd->cuted_fields))
-    send_ok(thd,info.copied+info.deleted+info.updated,id);
+  {
+    thd->row_count_func= info.copied+info.deleted+info.updated;
+    send_ok(thd, thd->row_count_func, id);
+  }
   else
   {
     char buff[160];
@@ -430,7 +433,8 @@ int mysql_insert(THD *thd,TABLE_LIST *table_list,
     else
       sprintf(buff, ER(ER_INSERT_INFO), (ulong) info.records,
 	      (ulong) info.deleted+info.updated, (ulong) thd->cuted_fields);
-    ::send_ok(thd,info.copied+info.deleted+info.updated,(ulonglong)id,buff);
+    thd->row_count_func= info.copied+info.deleted+info.updated;
+    ::send_ok(thd, thd->row_count_func, (ulonglong)id,buff);
   }
   free_underlaid_joins(thd, &thd->lex->select_lex);
   table->insert_values=0;
@@ -1565,7 +1569,8 @@ bool select_insert::send_eof()
   else
     sprintf(buff, ER(ER_INSERT_INFO), (ulong) info.records,
 	    (ulong) info.deleted+info.updated, (ulong) thd->cuted_fields);
-  ::send_ok(thd,info.copied+info.deleted+info.updated,last_insert_id,buff);
+  thd->row_count_func= info.copied+info.deleted+info.updated;
+  ::send_ok(thd, thd->row_count_func, last_insert_id, buff);
   DBUG_RETURN(0);
 }
 

sql/sql_parse.cc

@@ -3582,7 +3582,7 @@ mysql_execute_command(THD *thd)
 	}
 
 	if (res == 0)
-	  send_ok(thd);
+	  send_ok(thd, thd->row_count_func);
 	else
 	  goto error;		// Substatement should already have sent error
       }

sql/sql_update.cc

@@ -399,8 +399,9 @@ int mysql_update(THD *thd,
     char buff[80];
     sprintf(buff, ER(ER_UPDATE_INFO), (ulong) found, (ulong) updated,
 	    (ulong) thd->cuted_fields);
-    send_ok(thd,
-	    (thd->client_capabilities & CLIENT_FOUND_ROWS) ? found : updated,
+    thd->row_count_func=
+      (thd->client_capabilities & CLIENT_FOUND_ROWS) ? found : updated;
+    send_ok(thd, thd->row_count_func,
 	    thd->insert_id_used ? thd->insert_id() : 0L,buff);
     DBUG_PRINT("info",("%d records updated",updated));
   }
@@ -1124,8 +1125,9 @@ bool multi_update::send_eof()
 
   sprintf(buff, ER(ER_UPDATE_INFO), (ulong) found, (ulong) updated,
 	  (ulong) thd->cuted_fields);
-  ::send_ok(thd,
-	    (thd->client_capabilities & CLIENT_FOUND_ROWS) ? found : updated,
+  thd->row_count_func=
+    (thd->client_capabilities & CLIENT_FOUND_ROWS) ? found : updated;
+  ::send_ok(thd, thd->row_count_func,
 	    thd->insert_id_used ? thd->insert_id() : 0L,buff);
   return 0;
 }

sql/sql_yacc.yy

@@ -436,6 +436,7 @@ bool my_yyoverflow(short **a, YYSTYPE **b,int *yystacksize);
 %token	X509_SYM
 %token	XOR
 %token	COMPRESSED_SYM
+%token  ROW_COUNT_SYM
 
 %token  ERRORS
 %token  WARNINGS
@@ -3936,6 +3937,11 @@ simple_expr:
 	| ROUND '(' expr ')'
 	  { $$= new Item_func_round($3, new Item_int((char*)"0",0,1),0); }
 	| ROUND '(' expr ',' expr ')' { $$= new Item_func_round($3,$5,0); }
+	| ROW_COUNT_SYM '(' ')'
+	  {
+	    $$= new Item_func_row_count();
+	    Lex->safe_to_cache_query= 0;
+	  }
 	| SUBDATE_SYM '(' expr ',' expr ')'
 	  { $$= new Item_date_add_interval($3, $5, INTERVAL_DAY, 1);}
 	| SUBDATE_SYM '(' expr ',' INTERVAL_SYM expr interval ')'