Added CHECK_FIELD_EXPRESSION

This is needed for MDEV 13679 Enabled sequences to be used in DEFAULT

Added new option for count_cuted_fields: CHECK_FIELD_EXPRESSION
which is used to check if a DEFAULT expression is correct before
ALTER TABLE starts

Changed also all test:
  if (thd->count_cuted_fields)
  to
  if (thd->count_cuted_fields > CHECK_FIELD_EXPRESSION)

sql/field.cc

@@ -1518,7 +1518,7 @@ bool Field_num::get_int(CHARSET_INFO *cs, const char *from, uint len,
       goto out_of_range;
     }
   }
-  if (get_thd()->count_cuted_fields &&
+  if (get_thd()->count_cuted_fields > CHECK_FIELD_EXPRESSION &&
       check_int(cs, from, len, end, error))
     return 1;
   return 0;
@@ -1539,7 +1539,7 @@ double Field_real::get_double(const char *str, uint length, CHARSET_INFO *cs,
     set_warning(ER_WARN_DATA_OUT_OF_RANGE, 1);
     *error= 1;
   }
-  else if (get_thd()->count_cuted_fields &&
+  else if (get_thd()->count_cuted_fields > CHECK_FIELD_EXPRESSION &&
            check_edom_and_truncation("double", str == end,
                                      cs, str, length, end))
     *error= 1;
@@ -2492,7 +2492,7 @@ int Field_decimal::store(const char *from_arg, uint len, CHARSET_INFO *cs)
     it makes the code easer to read.
   */
 
-  if (get_thd()->count_cuted_fields)
+  if (get_thd()->count_cuted_fields > CHECK_FIELD_EXPRESSION)
   {
     // Skip end spaces
     for (;from != end && my_isspace(&my_charset_bin, *from); from++) ;
@@ -2662,7 +2662,8 @@ int Field_decimal::store(const char *from_arg, uint len, CHARSET_INFO *cs)
     {
       if (pos == right_wall) 
       {
-        if (get_thd()->count_cuted_fields && !is_cuted_fields_incr) 
+        if (get_thd()->count_cuted_fields > CHECK_FIELD_EXPRESSION &&
+            !is_cuted_fields_incr)
           break; // Go on below to see if we lose non zero digits
         return 0;
       }
@@ -3055,7 +3056,7 @@ int Field_new_decimal::store(const char *from, uint length,
     DBUG_RETURN(1);
   }
 
-  if (thd->count_cuted_fields)
+  if (thd->count_cuted_fields > CHECK_FIELD_EXPRESSION)
   {
     if (check_edom_and_important_data_truncation("decimal",
                                                  err && err != E_DEC_TRUNCATED,
@@ -3100,7 +3101,7 @@ int Field_new_decimal::store(const char *from, uint length,
     - in err2: store_value() truncated 1.123 to 1.12, e.g. for DECIMAL(10,2)
     Also, we send a note if a string had some trailing spaces: '1.12 '
   */
-  if (thd->count_cuted_fields &&
+  if (thd->count_cuted_fields > CHECK_FIELD_EXPRESSION &&
       (err == E_DEC_TRUNCATED ||
        err2 == E_DEC_TRUNCATED ||
        end < from + length))
@@ -4177,7 +4178,7 @@ int Field_longlong::store(const char *from,uint len,CHARSET_INFO *cs)
     set_warning(ER_WARN_DATA_OUT_OF_RANGE, 1);
     error= 1;
   }
-  else if (get_thd()->count_cuted_fields && 
+  else if (get_thd()->count_cuted_fields > CHECK_FIELD_EXPRESSION &&
            check_int(cs, from, len, end, error))
     error= 1;
   else
@@ -6077,7 +6078,7 @@ int Field_year::store(const char *from, uint len,CHARSET_INFO *cs)
     set_warning(ER_WARN_DATA_OUT_OF_RANGE, 1);
     return 1;
   }
-  if (get_thd()->count_cuted_fields && 
+  if (get_thd()->count_cuted_fields > CHECK_FIELD_EXPRESSION &&
       (error= check_int(cs, from, len, end, error)))
   {
     if (error == 1)  /* empty or incorrect string */
@@ -6785,7 +6786,7 @@ Field_longstr::report_if_important_data(const char *pstr, const char *end,
                                         bool count_spaces)
 {
   THD *thd= get_thd();
-  if ((pstr < end) && thd->count_cuted_fields)
+  if ((pstr < end) && thd->count_cuted_fields > CHECK_FIELD_EXPRESSION)
   {
     if (test_if_important_data(field_charset, pstr, end))
     {
@@ -8859,7 +8860,7 @@ int Field_enum::store(const char *from,uint length,CHARSET_INFO *cs)
 	set_warning(WARN_DATA_TRUNCATED, 1);
 	err= 1;
       }
-      if (!get_thd()->count_cuted_fields && !length)
+      if ((get_thd()->count_cuted_fields <= CHECK_FIELD_EXPRESSION) && !length)
         err= 0;
     }
     else
@@ -8886,7 +8887,7 @@ int Field_enum::store(longlong nr, bool unsigned_val)
   if ((ulonglong) nr > typelib->count || nr == 0)
   {
     set_warning(WARN_DATA_TRUNCATED, 1);
-    if (nr != 0 || get_thd()->count_cuted_fields)
+    if (nr != 0 || get_thd()->count_cuted_fields > CHECK_FIELD_EXPRESSION)
     {
       nr= 0;
       error= 1;
@@ -10112,6 +10113,8 @@ bool check_expression(Virtual_column_info *vcol, LEX_CSTRING *name,
   uint filter= VCOL_IMPOSSIBLE;
   if (type != VCOL_GENERATED_VIRTUAL && type != VCOL_DEFAULT)
     filter|= VCOL_NOT_STRICTLY_DETERMINISTIC;
+  if (type == VCOL_GENERATED_VIRTUAL)
+    filter|= VCOL_NOT_VIRTUAL;
 
   if (ret || (res.errors & filter))
   {
@@ -10920,11 +10923,12 @@ uint32 Field_blob::max_display_length()
   @param cut_increment    - whenever we should increase cut fields count
 
   @note
-    This function won't produce warning and increase cut fields counter
-    if count_cuted_fields == CHECK_FIELD_IGNORE for current thread.
+    This function won't produce warning or notes or increase cut fields counter
+    if count_cuted_fields == CHECK_FIELD_IGNORE or CHECK_FIELD_EXPRESSION
+    for the current thread.
 
-    if count_cuted_fields == CHECK_FIELD_IGNORE then we ignore notes.
-    This allows us to avoid notes in optimisation, like convert_constant_item().
+    This allows us to avoid notes in optimisation, like
+    convert_constant_item().
 
   @retval
     1 if count_cuted_fields == CHECK_FIELD_IGNORE and error level is not NOTE
@@ -10941,7 +10945,7 @@ Field::set_warning(Sql_condition::enum_warning_level level, uint code,
     will have table == NULL.
   */
   THD *thd= get_thd();
-  if (thd->count_cuted_fields)
+  if (thd->count_cuted_fields > CHECK_FIELD_EXPRESSION)
   {
     thd->cuted_fields+= cut_increment;
     push_warning_printf(thd, level, code, ER_THD(thd, code), field_name.str,

sql/field.h

@@ -50,8 +50,9 @@ class Virtual_tmp_table;
 enum enum_check_fields
 {
   CHECK_FIELD_IGNORE,
+  CHECK_FIELD_EXPRESSION,
   CHECK_FIELD_WARN,
-  CHECK_FIELD_ERROR_FOR_NULL
+  CHECK_FIELD_ERROR_FOR_NULL,
 };
 
 /*
@@ -558,6 +559,7 @@ static inline const char *vcol_type_name(enum_vcol_info_type type)
 #define VCOL_TIME_FUNC         8
 #define VCOL_AUTO_INC         16
 #define VCOL_IMPOSSIBLE       32
+#define VCOL_NOT_VIRTUAL      64  /* Function can't be virtual */
 
 #define VCOL_NOT_STRICTLY_DETERMINISTIC                       \
   (VCOL_NON_DETERMINISTIC | VCOL_TIME_FUNC | VCOL_SESSION_FUNC)

sql/field_conv.cc

@@ -122,6 +122,7 @@ static int set_bad_null_error(Field *field, int err)
     field->set_warning(Sql_condition::WARN_LEVEL_WARN, err, 1);
     /* fall through */
   case CHECK_FIELD_IGNORE:
+  case CHECK_FIELD_EXPRESSION:
     return 0;
   case CHECK_FIELD_ERROR_FOR_NULL:
     if (!field->table->in_use->no_errors)
@@ -528,7 +529,8 @@ static void do_varstring1(Copy_field *copy)
   if (length > copy->to_length- 1)
   {
     length=copy->to_length - 1;
-    if (copy->from_field->table->in_use->count_cuted_fields &&
+    if (copy->from_field->table->in_use->count_cuted_fields >
+        CHECK_FIELD_EXPRESSION &&
         copy->to_field)
       copy->to_field->set_warning(Sql_condition::WARN_LEVEL_WARN,
                                   WARN_DATA_TRUNCATED, 1);
@@ -547,7 +549,7 @@ static void do_varstring1_mb(Copy_field *copy)
   Well_formed_prefix prefix(cs, (char*) from_ptr, from_length, to_char_length);
   if (prefix.length() < from_length)
   {
-    if (current_thd->count_cuted_fields)
+    if (current_thd->count_cuted_fields > CHECK_FIELD_EXPRESSION)
       copy->to_field->set_warning(Sql_condition::WARN_LEVEL_WARN,
                                   WARN_DATA_TRUNCATED, 1);
   }
@@ -562,7 +564,8 @@ static void do_varstring2(Copy_field *copy)
   if (length > copy->to_length- HA_KEY_BLOB_LENGTH)
   {
     length=copy->to_length-HA_KEY_BLOB_LENGTH;
-    if (copy->from_field->table->in_use->count_cuted_fields &&
+    if (copy->from_field->table->in_use->count_cuted_fields >
+        CHECK_FIELD_EXPRESSION &&
         copy->to_field)
       copy->to_field->set_warning(Sql_condition::WARN_LEVEL_WARN,
                                   WARN_DATA_TRUNCATED, 1);
@@ -582,7 +585,7 @@ static void do_varstring2_mb(Copy_field *copy)
   Well_formed_prefix prefix(cs, (char*) from_beg, from_length, char_length);
   if (prefix.length() < from_length)
   {
-    if (current_thd->count_cuted_fields)
+    if (current_thd->count_cuted_fields > CHECK_FIELD_EXPRESSION)
       copy->to_field->set_warning(Sql_condition::WARN_LEVEL_WARN,
                                   WARN_DATA_TRUNCATED, 1);
   }  

sql/sql_table.cc

@@ -9311,10 +9311,12 @@ bool mysql_alter_table(THD *thd, const char *new_db, const char *new_name,
                                                 &altered_table->s->all_set);
     restore_record(altered_table, s->default_values); // Create empty record
     /* Check that we can call default functions with default field values */
+    thd->count_cuted_fields= CHECK_FIELD_EXPRESSION;
     altered_table->reset_default_fields();
     if (altered_table->default_field &&
         altered_table->update_default_fields(0, 1))
       goto err_new_table_cleanup;
+    thd->count_cuted_fields= CHECK_FIELD_IGNORE;
 
     // Ask storage engine whether to use copy or in-place
     enum_alter_inplace_result inplace_supported=