MDEV-13003 - Oracle compatibility : Replace function

mysql-test/suite/compat/oracle/r/func_replace.result

+SET sql_mode=ORACLE;
+#
+# MDEV-13003 - Oracle compatibility : Replace function
+#
+SELECT REPLACE(null,'a','b') ;
+REPLACE(null,'a','b')
+NULL
+SELECT REPLACE('ab',null,'b') ;
+REPLACE('ab',null,'b')
+ab
+SELECT REPLACE('ab','a',null) ;
+REPLACE('ab','a',null)
+b
+SELECT REPLACE('ab',null,null) ;
+REPLACE('ab',null,null)
+ab
+SELECT REPLACE('aaa','a',null) ;
+REPLACE('aaa','a',null)
+NULL
+EXPLAIN EXTENDED SELECT REPLACE('ab','a',null) ;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	No tables used
+Warnings:
+Note	1003	select replace_oracle('ab','a',NULL) AS "REPLACE('ab','a',null)"
+CREATE VIEW v1 AS SELECT REPLACE('ab','a',null) ;
+SHOW CREATE VIEW v1;
+View	Create View	character_set_client	collation_connection
+v1	CREATE VIEW "v1" AS select replace_oracle('ab','a',NULL) AS "REPLACE('ab','a',null)"	latin1	latin1_swedish_ci
+SELECT * FROM v1;
+REPLACE('ab','a',null)
+b
+DROP VIEW v1;

mysql-test/suite/compat/oracle/t/func_replace.test

+#
+# Testing replace with null args
+#
+
+SET sql_mode=ORACLE;
+
+--echo #
+--echo # MDEV-13003 - Oracle compatibility : Replace function
+--echo #
+
+SELECT REPLACE(null,'a','b') ;
+SELECT REPLACE('ab',null,'b') ;
+SELECT REPLACE('ab','a',null) ;
+SELECT REPLACE('ab',null,null) ;
+SELECT REPLACE('aaa','a',null) ;
+
+EXPLAIN EXTENDED SELECT REPLACE('ab','a',null) ;
+
+CREATE VIEW v1 AS SELECT REPLACE('ab','a',null) ;
+SHOW CREATE VIEW v1;
+SELECT * FROM v1;
+DROP VIEW v1;

sql/item_create.cc

@@ -2624,6 +2624,19 @@ class Create_func_release_lock : public Create_func_arg1
 };
 
 
+class Create_func_replace_oracle : public Create_func_arg3
+{
+public:
+  virtual Item *create_3_arg(THD *thd, Item *arg1, Item *arg2, Item *arg3);
+
+  static Create_func_replace_oracle s_singleton;
+
+protected:
+  Create_func_replace_oracle() {}
+  virtual ~Create_func_replace_oracle() {}
+};
+
+
 class Create_func_reverse : public Create_func_arg1
 {
 public:
@@ -6214,6 +6227,16 @@ Create_func_release_lock::create_1_arg(THD *thd, Item *arg1)
 }
 
 
+Create_func_replace_oracle Create_func_replace_oracle::s_singleton;
+
+Item*
+Create_func_replace_oracle::create_3_arg(THD *thd, Item *arg1, Item *arg2,
+                                        Item *arg3)
+{
+  return new (thd->mem_root) Item_func_replace_oracle(thd, arg1, arg2, arg3);
+}
+
+
 Create_func_reverse Create_func_reverse::s_singleton;
 
 Item*
@@ -6802,6 +6825,7 @@ static Native_func_registry func_array[] =
   { { C_STRING_WITH_LEN("CENTROID") }, GEOM_BUILDER(Create_func_centroid)},
   { { C_STRING_WITH_LEN("CHARACTER_LENGTH") }, BUILDER(Create_func_char_length)},
   { { C_STRING_WITH_LEN("CHAR_LENGTH") }, BUILDER(Create_func_char_length)},
+  { { C_STRING_WITH_LEN("CHR") }, BUILDER(Create_func_chr)},
   { { C_STRING_WITH_LEN("COERCIBILITY") }, BUILDER(Create_func_coercibility)},
   { { C_STRING_WITH_LEN("COLUMN_CHECK") }, BUILDER(Create_func_dyncol_check)},
   { { C_STRING_WITH_LEN("COLUMN_EXISTS") }, BUILDER(Create_func_dyncol_exists)},
@@ -6815,7 +6839,6 @@ static Native_func_registry func_array[] =
   { { C_STRING_WITH_LEN("CONV") }, BUILDER(Create_func_conv)},
   { { C_STRING_WITH_LEN("CONVERT_TZ") }, BUILDER(Create_func_convert_tz)},
   { { C_STRING_WITH_LEN("CONVEXHULL") }, GEOM_BUILDER(Create_func_convexhull)},
-  { { C_STRING_WITH_LEN("CHR") }, BUILDER(Create_func_chr)},
   { { C_STRING_WITH_LEN("COS") }, BUILDER(Create_func_cos)},
   { { C_STRING_WITH_LEN("COT") }, BUILDER(Create_func_cot)},
   { { C_STRING_WITH_LEN("CRC32") }, BUILDER(Create_func_crc32)},
@@ -6990,6 +7013,8 @@ static Native_func_registry func_array[] =
   { { C_STRING_WITH_LEN("RADIANS") }, BUILDER(Create_func_radians)},
   { { C_STRING_WITH_LEN("RAND") }, BUILDER(Create_func_rand)},
   { { C_STRING_WITH_LEN("RELEASE_LOCK") }, BUILDER(Create_func_release_lock)},
+  { { C_STRING_WITH_LEN("REPLACE_ORACLE") },
+      BUILDER(Create_func_replace_oracle)},
   { { C_STRING_WITH_LEN("REVERSE") }, BUILDER(Create_func_reverse)},
   { { C_STRING_WITH_LEN("ROUND") }, BUILDER(Create_func_round)},
   { { C_STRING_WITH_LEN("RPAD") }, BUILDER(Create_func_rpad)},

sql/item_strfunc.cc

@@ -1205,7 +1205,8 @@ void Item_func_reverse::fix_length_and_dec()
     Fix that this works with binary strings when using USE_MB 
 */
 
-String *Item_func_replace::val_str(String *str)
+String *Item_func_replace::val_str_internal(String *str,
+                                            String *empty_string_for_null)
 {
   DBUG_ASSERT(fixed == 1);
   String *res,*res2,*res3;
@@ -1225,8 +1226,11 @@ String *Item_func_replace::val_str(String *str)
     goto null;
   res2=args[1]->val_str(&tmp_value);
   if (args[1]->null_value)
-    goto null;
-
+  {
+    if (!empty_string_for_null)
+      goto null;
+    res2= empty_string_for_null;
+  }
   res->set_charset(collation.collation);
 
 #ifdef USE_MB
@@ -1244,7 +1248,11 @@ String *Item_func_replace::val_str(String *str)
     return res;
 #endif
   if (!(res3=args[2]->val_str(&tmp_value2)))
-    goto null;
+  {
+    if (!empty_string_for_null)
+      goto null;
+    res3= empty_string_for_null;
+  }
   from_length= res2->length();
   to_length=   res3->length();
 
@@ -1327,6 +1335,9 @@ String *Item_func_replace::val_str(String *str)
     }
     while ((offset=res->strstr(*res2,(uint) offset)) >= 0);
   }
+  if (empty_string_for_null && !res->length())
+    goto null;
+
   return res;
 
 null:

sql/item_strfunc.h

@@ -359,14 +359,28 @@ class Item_func_replace :public Item_str_func
 public:
   Item_func_replace(THD *thd, Item *org, Item *find, Item *replace):
     Item_str_func(thd, org, find, replace) {}
-  String *val_str(String *);
+  String *val_str(String *to) { return val_str_internal(to, NULL); };
   void fix_length_and_dec();
+  String *val_str_internal(String *str, String *empty_string_for_null);
   const char *func_name() const { return "replace"; }
   Item *get_copy(THD *thd, MEM_ROOT *mem_root)
   { return get_item_copy<Item_func_replace>(thd, mem_root, this); }
 };
 
 
+class Item_func_replace_oracle :public Item_func_replace
+{
+  String tmp_emtpystr;
+public:
+  Item_func_replace_oracle(THD *thd, Item *org, Item *find, Item *replace):
+    Item_func_replace(thd, org, find, replace) {}
+  String *val_str(String *to) { return val_str_internal(to, &tmp_emtpystr); };
+  const char *func_name() const { return "replace_oracle"; }
+  Item *get_copy(THD *thd, MEM_ROOT *mem_root)
+  { return get_item_copy<Item_func_replace_oracle>(thd, mem_root, this); }
+};
+
+
 class Item_func_regexp_replace :public Item_str_func
 {
   Regexp_processor_pcre re;

sql/sql_lex.cc

@@ -7161,3 +7161,14 @@ bool LEX::add_grant_command(THD *thd, enum_sql_command sql_command_arg,
   type= type_arg;
   return false;
 }
+
+
+Item *LEX::make_item_func_replace(THD *thd,
+                                  Item *org,
+                                  Item *find,
+                                  Item *replace)
+{
+  return (thd->variables.sql_mode & MODE_ORACLE) ?
+    new (thd->mem_root) Item_func_replace_oracle(thd, org, find, replace) :
+    new (thd->mem_root) Item_func_replace(thd, org, find, replace);
+}

sql/sql_lex.h

@@ -3357,6 +3357,8 @@ struct LEX: public Query_tables_list
                           const LEX_CSTRING *field_name,
                           uint pos_in_q, uint length_in_q);
 
+  Item *make_item_func_replace(THD *thd, Item *org, Item *find, Item *replace);
+
   /*
     Create a my_var instance for a ROW field variable that was used
     as an OUT SP parameter: CALL p1(var.field);

sql/sql_yacc.yy

@@ -10083,8 +10083,7 @@ function_call_conflict:
           }
         | REPLACE '(' expr ',' expr ',' expr ')'
           {
-            $$= new (thd->mem_root) Item_func_replace(thd, $3, $5, $7);
-            if ($$ == NULL)
+            if (!($$= Lex->make_item_func_replace(thd, $3, $5, $7)))
               MYSQL_YYABORT;
           }
         | REVERSE_SYM '(' expr ')'

sql/sql_yacc_ora.yy

@@ -10120,8 +10120,7 @@ function_call_conflict:
           }
         | REPLACE '(' expr ',' expr ',' expr ')'
           {
-            $$= new (thd->mem_root) Item_func_replace(thd, $3, $5, $7);
-            if ($$ == NULL)
+            if (!($$= Lex->make_item_func_replace(thd, $3, $5, $7)))
               MYSQL_YYABORT;
           }
         | REVERSE_SYM '(' expr ')'