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-rw-r--r--sql/field.cc144
1 files changed, 94 insertions, 50 deletions
diff --git a/sql/field.cc b/sql/field.cc
index ed085de1db3..9f46552d5bd 100644
--- a/sql/field.cc
+++ b/sql/field.cc
@@ -1922,16 +1922,16 @@ int Field_decimal::store(const char *from_arg, uint len, CHARSET_INFO *cs)
Pointers used when digits move from the left of the '.' to the
right of the '.' (explained below)
*/
- const uchar *int_digits_tail_from;
+ const uchar *UNINIT_VAR(int_digits_tail_from);
/* Number of 0 that need to be added at the left of the '.' (1E3: 3 zeros) */
- uint int_digits_added_zeros;
+ uint UNINIT_VAR(int_digits_added_zeros);
/*
Pointer used when digits move from the right of the '.' to the left
of the '.'
*/
- const uchar *frac_digits_head_end;
+ const uchar *UNINIT_VAR(frac_digits_head_end);
/* Number of 0 that need to be added at the right of the '.' (for 1E-3) */
- uint frac_digits_added_zeros;
+ uint UNINIT_VAR(frac_digits_added_zeros);
uchar *pos,*tmp_left_pos,*tmp_right_pos;
/* Pointers that are used as limits (begin and end of the field buffer) */
uchar *left_wall,*right_wall;
@@ -1942,11 +1942,6 @@ int Field_decimal::store(const char *from_arg, uint len, CHARSET_INFO *cs)
*/
bool is_cuted_fields_incr=0;
- LINT_INIT(int_digits_tail_from);
- LINT_INIT(int_digits_added_zeros);
- LINT_INIT(frac_digits_head_end);
- LINT_INIT(frac_digits_added_zeros);
-
/*
There are three steps in this function :
- parse the input string
@@ -2485,12 +2480,97 @@ Field_new_decimal::Field_new_decimal(uint32 len_arg,
{
precision= my_decimal_length_to_precision(len_arg, dec_arg, unsigned_arg);
set_if_smaller(precision, DECIMAL_MAX_PRECISION);
+ DBUG_ASSERT(precision >= dec);
DBUG_ASSERT((precision <= DECIMAL_MAX_PRECISION) &&
(dec <= DECIMAL_MAX_SCALE));
bin_size= my_decimal_get_binary_size(precision, dec);
}
+/**
+ Create a field to hold a decimal value from an item.
+
+ @remark The MySQL DECIMAL data type has a characteristic that needs to be
+ taken into account when deducing the type from a Item_decimal.
+
+ But first, let's briefly recap what is the new MySQL DECIMAL type:
+
+ The declaration syntax for a decimal is DECIMAL(M,D), where:
+
+ * M is the maximum number of digits (the precision).
+ It has a range of 1 to 65.
+ * D is the number of digits to the right of the decimal separator (the scale).
+ It has a range of 0 to 30 and must be no larger than M.
+
+ D and M are used to determine the storage requirements for the integer
+ and fractional parts of each value. The integer part is to the left of
+ the decimal separator and to the right is the fractional part. Hence:
+
+ M is the number of digits for the integer and fractional part.
+ D is the number of digits for the fractional part.
+
+ Consequently, M - D is the number of digits for the integer part. For
+ example, a DECIMAL(20,10) column has ten digits on either side of
+ the decimal separator.
+
+ The characteristic that needs to be taken into account is that the
+ backing type for Item_decimal is a my_decimal that has a higher
+ precision (DECIMAL_MAX_POSSIBLE_PRECISION, see my_decimal.h) than
+ DECIMAL.
+
+ Drawing a comparison between my_decimal and DECIMAL:
+
+ * M has a range of 1 to 81.
+ * D has a range of 0 to 81.
+
+ There can be a difference in range if the decimal contains a integer
+ part. This is because the fractional part must always be on a group
+ boundary, leaving at least one group for the integer part. Since each
+ group is 9 (DIG_PER_DEC1) digits and there are 9 (DECIMAL_BUFF_LENGTH)
+ groups, the fractional part is limited to 72 digits if there is at
+ least one digit in the integral part.
+
+ Although the backing type for a DECIMAL is also my_decimal, every
+ time a my_decimal is stored in a DECIMAL field, the precision and
+ scale are explicitly capped at 65 (DECIMAL_MAX_PRECISION) and 30
+ (DECIMAL_MAX_SCALE) digits, following my_decimal truncation procedure
+ (FIX_INTG_FRAC_ERROR).
+*/
+
+Field_new_decimal *
+Field_new_decimal::new_decimal_field(const Item *item)
+{
+ uint32 len;
+ uint intg= item->decimal_int_part(), scale= item->decimals;
+
+ DBUG_ASSERT(item->decimal_precision() >= item->decimals);
+
+ /*
+ Employ a procedure along the lines of the my_decimal truncation process:
+ - If the integer part is equal to or bigger than the maximum precision:
+ Truncate integer part to fit and the fractional becomes zero.
+ - Otherwise:
+ Truncate fractional part to fit.
+ */
+ if (intg >= DECIMAL_MAX_PRECISION)
+ {
+ intg= DECIMAL_MAX_PRECISION;
+ scale= 0;
+ }
+ else
+ {
+ uint room= min(DECIMAL_MAX_PRECISION - intg, DECIMAL_MAX_SCALE);
+ if (scale > room)
+ scale= room;
+ }
+
+ len= my_decimal_precision_to_length(intg + scale, scale, item->unsigned_flag);
+
+ return new Field_new_decimal(len, item->maybe_null, item->name, scale,
+ item->unsigned_flag);
+}
+
+
int Field_new_decimal::reset(void)
{
store_value(&decimal_zero);
@@ -4598,7 +4678,6 @@ bool Field_double::send_binary(Protocol *protocol)
int Field_double::cmp(const uchar *a_ptr, const uchar *b_ptr)
{
- ASSERT_COLUMN_MARKED_FOR_READ;
double a,b;
#ifdef WORDS_BIGENDIAN
if (table->s->db_low_byte_first)
@@ -6271,48 +6350,15 @@ check_string_copy_error(Field_str *field,
const char *end,
CHARSET_INFO *cs)
{
- const char *pos, *end_orig;
- char tmp[64], *t;
+ const char *pos;
+ char tmp[32];
if (!(pos= well_formed_error_pos) &&
!(pos= cannot_convert_error_pos))
return FALSE;
- end_orig= end;
- set_if_smaller(end, pos + 6);
+ convert_to_printable(tmp, sizeof(tmp), pos, (end - pos), cs, 6);
- for (t= tmp; pos < end; pos++)
- {
- /*
- If the source string is ASCII compatible (mbminlen==1)
- and the source character is in ASCII printable range (0x20..0x7F),
- then display the character as is.
-
- Otherwise, if the source string is not ASCII compatible (e.g. UCS2),
- or the source character is not in the printable range,
- then print the character using HEX notation.
- */
- if (((unsigned char) *pos) >= 0x20 &&
- ((unsigned char) *pos) <= 0x7F &&
- cs->mbminlen == 1)
- {
- *t++= *pos;
- }
- else
- {
- *t++= '\\';
- *t++= 'x';
- *t++= _dig_vec_upper[((unsigned char) *pos) >> 4];
- *t++= _dig_vec_upper[((unsigned char) *pos) & 15];
- }
- }
- if (end_orig > end)
- {
- *t++= '.';
- *t++= '.';
- *t++= '.';
- }
- *t= '\0';
push_warning_printf(field->table->in_use,
field->table->in_use->abort_on_warning ?
MYSQL_ERROR::WARN_LEVEL_ERROR :
@@ -9951,10 +9997,8 @@ Field *make_field(TABLE_SHARE *share, uchar *ptr, uint32 field_length,
TYPELIB *interval,
const char *field_name)
{
- uchar *bit_ptr;
- uchar bit_offset;
- LINT_INIT(bit_ptr);
- LINT_INIT(bit_offset);
+ uchar *UNINIT_VAR(bit_ptr);
+ uchar UNINIT_VAR(bit_offset);
if (field_type == MYSQL_TYPE_BIT && !f_bit_as_char(pack_flag))
{
bit_ptr= null_pos;