diff options
Diffstat (limited to 'sql/field.h')
| -rw-r--r-- | sql/field.h | 58 |
1 files changed, 38 insertions, 20 deletions
diff --git a/sql/field.h b/sql/field.h index 8c46633d550..0af2150adfa 100644 --- a/sql/field.h +++ b/sql/field.h @@ -1503,13 +1503,16 @@ public: /* maximum possible display length */ virtual uint32 max_display_length() const= 0; /** - Whether a field being created is compatible with a existing one. - - Used by the ALTER TABLE code to evaluate whether the new definition - of a table is compatible with the old definition so that it can - determine if data needs to be copied over (table data change). + Whether a field being created has the samle type. + Used by the ALTER TABLE */ - virtual uint is_equal(Create_field *new_field)= 0; + virtual bool is_equal(const Column_definition &new_field) const= 0; + // Used as double dispatch pattern: calls virtual method of handler + virtual bool + can_be_converted_by_engine(const Column_definition &new_type) const + { + return false; + } /* convert decimal to longlong with overflow check */ longlong convert_decimal2longlong(const my_decimal *val, bool unsigned_flag, int *err); @@ -1809,7 +1812,7 @@ public: !((flags & UNSIGNED_FLAG) && !(from->flags & UNSIGNED_FLAG)) && decimals() == from->decimals(); } - uint is_equal(Create_field *new_field); + bool is_equal(const Column_definition &new_field) const; uint row_pack_length() const { return pack_length(); } uint32 pack_length_from_metadata(uint field_metadata) { uint32 length= pack_length(); @@ -1874,7 +1877,7 @@ public: bool val_bool() { return val_real() != 0e0; } virtual bool str_needs_quotes() { return TRUE; } bool eq_cmp_as_binary() { return MY_TEST(flags & BINARY_FLAG); } - virtual uint length_size() { return 0; } + virtual uint length_size() const { return 0; } double pos_in_interval(Field *min, Field *max) { return pos_in_interval_val_str(min, max, length_size()); @@ -1928,8 +1931,6 @@ protected: CHARSET_INFO *cs, size_t nchars); String *uncompress(String *val_buffer, String *val_ptr, const uchar *from, uint from_length); - uint is_equal_for_different_charsets(const Column_definition &to) const; - public: Field_longstr(uchar *ptr_arg, uint32 len_arg, uchar *null_ptr_arg, uchar null_bit_arg, utype unireg_check_arg, @@ -2142,7 +2143,7 @@ public: uint row_pack_length() const { return pack_length(); } bool compatible_field_size(uint field_metadata, Relay_log_info *rli, uint16 mflags, int *order_var); - uint is_equal(Create_field *new_field); + bool is_equal(const Column_definition &new_field) const; virtual const uchar *unpack(uchar* to, const uchar *from, const uchar *from_end, uint param_data); Item *get_equal_const_item(THD *thd, const Context &ctx, Item *const_item); }; @@ -2646,7 +2647,7 @@ public: my_decimal *val_decimal(my_decimal *) { return 0; } String *val_str(String *value,String *value2) { value2->length(0); return value2;} - uint is_equal(Create_field *new_field); + bool is_equal(const Column_definition &new_field) const; int cmp(const uchar *a, const uchar *b) { return 0;} void sort_string(uchar *buff, uint length) {} uint32 pack_length() const { return 0; } @@ -2729,7 +2730,7 @@ public: CHARSET_INFO *sort_charset(void) const { return &my_charset_bin; } bool binary() const { return true; } bool val_bool() { return val_real() != 0e0; } - uint is_equal(Create_field *new_field); + bool is_equal(const Column_definition &new_field) const; bool eq_def(const Field *field) const { return (Field::eq_def(field) && decimals() == field->decimals()); @@ -3570,7 +3571,11 @@ public: int cmp(const uchar *,const uchar *); void sort_string(uchar *buff,uint length); void sql_type(String &str) const; - uint is_equal(Create_field *new_field); + bool is_equal(const Column_definition &new_field) const; + bool can_be_converted_by_engine(const Column_definition &new_type) const + { + return table->file->can_convert_string(this, new_type); + } virtual uchar *pack(uchar *to, const uchar *from, uint max_length); virtual const uchar *unpack(uchar* to, const uchar *from, @@ -3698,9 +3703,13 @@ public: Field *new_key_field(MEM_ROOT *root, TABLE *new_table, uchar *new_ptr, uint32 length, uchar *new_null_ptr, uint new_null_bit); - uint is_equal(Create_field *new_field); + bool is_equal(const Column_definition &new_field) const; + bool can_be_converted_by_engine(const Column_definition &new_type) const + { + return table->file->can_convert_varstring(this, new_type); + } void hash(ulong *nr, ulong *nr2); - uint length_size() { return length_bytes; } + uint length_size() const { return length_bytes; } void print_key_value(String *out, uint32 length); private: int save_field_metadata(uchar *first_byte); @@ -4039,7 +4048,11 @@ public: uint32 max_display_length() const; uint32 char_length() const; uint32 character_octet_length() const; - uint is_equal(Create_field *new_field); + bool is_equal(const Column_definition &new_field) const; + bool can_be_converted_by_engine(const Column_definition &new_type) const + { + return table->file->can_convert_blob(this, new_type); + } void print_key_value(String *out, uint32 length); friend void TABLE::remember_blob_values(String *blob_storage); @@ -4154,7 +4167,12 @@ public: geom_type == static_cast<const Field_geom*>(from)->geom_type) && !table->copy_blobs; } - uint is_equal(Create_field *new_field); + bool is_equal(const Column_definition &new_field) const; + bool can_be_converted_by_engine(const Column_definition &new_type) const + { + return table->file->can_convert_geom(this, new_type); + } + int store(const char *to, size_t length, CHARSET_INFO *charset); int store(double nr); int store(longlong nr, bool unsigned_val); @@ -4298,7 +4316,7 @@ public: bool is_eq_func) const; private: int save_field_metadata(uchar *first_byte); - uint is_equal(Create_field *new_field); + bool is_equal(const Column_definition &new_field) const; }; @@ -4477,7 +4495,7 @@ public: bit_ptr == ((Field_bit *)field)->bit_ptr && bit_ofs == ((Field_bit *)field)->bit_ofs); } - uint is_equal(Create_field *new_field); + bool is_equal(const Column_definition &new_field) const; void move_field_offset(my_ptrdiff_t ptr_diff) { Field::move_field_offset(ptr_diff); |