WL#1253: LAST_DAY

mysql-test/r/func_time.result:
  Test for WL#1253: LAST_DAY
mysql-test/t/func_time.test:
  Test for WL#1253: LAST_DAY

mysql-test/r/func_time.result

@@ -468,6 +468,23 @@ select date_add(time,INTERVAL 1 SECOND) from t1;
 date_add(time,INTERVAL 1 SECOND)
 2006-07-08 00:00:01
 drop table t1;
+select last_day('2000-02-05') as f1, last_day('2002-12-31') as f2,
+last_day('2003-03-32') as f3, last_day('2003-04-01') as f4,
+last_day('2001-01-01 01:01:01') as f5, last_day(NULL),
+last_day('2001-02-12');
+f1	f2	f3	f4	f5	last_day(NULL)	last_day('2001-02-12')
+2000-02-29	2002-12-31	NULL	2003-04-30	2001-01-31	NULL	2001-02-28
+create table t1 select last_day('2000-02-05') as a;
+describe t1;
+Field	Type	Null	Key	Default	Extra
+a	date			0000-00-00	
+select * from t1;
+a
+2000-02-29
+drop table t1;
+select last_day('2000-02-05');
+last_day('2000-02-05')
+2000-02-29
 select strcmp(date_sub(localtimestamp(), interval 3 hour), utc_timestamp())=0;
 strcmp(date_sub(localtimestamp(), interval 3 hour), utc_timestamp())=0
 1

mysql-test/t/func_time.test

@@ -224,6 +224,19 @@ select date_add(date,INTERVAL "1 1:1:1" DAY_SECOND) from t1;
 select date_add(time,INTERVAL 1 SECOND) from t1;
 drop table t1;
 
+# test for last_day
+select last_day('2000-02-05') as f1, last_day('2002-12-31') as f2,
+       last_day('2003-03-32') as f3, last_day('2003-04-01') as f4,
+       last_day('2001-01-01 01:01:01') as f5, last_day(NULL),
+       last_day('2001-02-12');
+
+create table t1 select last_day('2000-02-05') as a;
+describe t1;
+select * from t1;
+drop table t1;
+select last_day('2000-02-05');
+
+
 # Test SAPDB UTC_% functions. This part is TZ dependant (It is supposed that
 # TZ variable set to GMT-3
 select strcmp(date_sub(localtimestamp(), interval 3 hour), utc_timestamp())=0;

sql/item_create.cc

@@ -707,3 +707,8 @@ Item *create_func_str_to_date(Item* a,Item* b)
 {
   return new Item_func_str_to_date(a, b);
 }
+
+Item *create_func_last_day(Item *a)
+{
+  return new Item_func_last_day(a);
+}

sql/item_create.h

@@ -150,3 +150,4 @@ Item *create_func_subtime(Item* a,Item* b);
 Item *create_func_timediff(Item* a,Item* b);
 Item *create_func_maketime(Item* a,Item* b,Item* c);
 Item *create_func_str_to_date(Item* a,Item* b);
+Item *create_func_last_day(Item *a);

sql/item_timefunc.cc

@@ -2310,3 +2310,19 @@ String *Item_func_str_to_date::val_str(String *str)
     return str;
   return 0;
 }
+
+
+String *Item_func_last_day::val_str(String *str)
+{
+  TIME ltime;
+  if (!get_arg0_date(&ltime,0))
+  {
+    uint month_idx= ltime.month-1;
+    ltime.day= days_in_month[month_idx];
+    if ( month_idx == 1 && calc_days_in_year(ltime.year) == 366)
+      ltime.day+= 1;
+    if (!make_datetime(DATE_ONLY, &ltime, str))
+      return str;      
+  }
+  return 0;
+}

sql/item_timefunc.h

@@ -809,3 +809,21 @@ class Item_func_str_to_date :public Item_date_func
     max_length=MAX_DATETIME_FULL_WIDTH*MY_CHARSET_BIN_MB_MAXLEN;
   }
 };
+
+class Item_func_last_day :public Item_str_func
+{
+public:
+  Item_func_last_day(Item *a) :Item_str_func(a) {}
+  String *val_str(String *str);
+  const char *func_name() const { return "last_day"; }
+  enum_field_types field_type() const { return MYSQL_TYPE_DATE; }
+  void fix_length_and_dec()
+  { 
+    decimals=0;
+    max_length=MAX_DATE_WIDTH*MY_CHARSET_BIN_MB_MAXLEN;
+  }
+  Field *tmp_table_field(TABLE *t_arg)
+  {
+    return (new Field_date(maybe_null, name, t_arg, &my_charset_bin));
+  }
+};

sql/lex.h

@@ -551,7 +551,8 @@ static SYMBOL sql_functions[] = {
   { "IS_FREE_LOCK",	SYM(FUNC_ARG1),0,CREATE_FUNC(create_func_is_free_lock)},
   { "IS_USED_LOCK",	SYM(FUNC_ARG1),0,CREATE_FUNC(create_func_is_used_lock)},
   { "LAST_INSERT_ID",	SYM(LAST_INSERT_ID),0,0},
-  { "ISSIMPLE",		SYM(FUNC_ARG1),0,CREATE_FUNC(create_func_issimple)},
+  { "ISSIMPLE",         SYM(FUNC_ARG1),0,CREATE_FUNC(create_func_issimple)},
+  { "LAST_DAY",         SYM(FUNC_ARG1),0,CREATE_FUNC(create_func_last_day)},
   { "LCASE",		SYM(FUNC_ARG1),0,CREATE_FUNC(create_func_lcase)},
   { "LEAST",		SYM(LEAST_SYM),0,0},
   { "LENGTH",		SYM(FUNC_ARG1),0,CREATE_FUNC(create_func_length)},