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3 commits

Author SHA1 Message Date
Alexander Barkov
07e4853c23 MDEV-17563 Different results using table or view when comparing values of time type
MDEV-17625 Different warnings when comparing a garbage to DATETIME vs TIME

- Splitting processes of data type conversion (to TIME/DATE,DATETIME)
  and warning generation.
  Warning are now only get collected during conversion (in an "int" variable),
  and are pushed in the very end of conversion (not in parallel).
  Warnings generated by the low level routines str_to_xxx() and number_to_xxx()
  can now be changed at the end, when TIME_FUZZY_DATES is applied,
  from "Invalid value" to "Truncated invalid value".

  Now "Illegal value" is issued only when the low level routine returned
  an error and TIME_FUZZY_DATES was not set. Otherwise, if the low level
  routine returned "false" (success), or if NULL was converted to a zero
  datetime by TIME_FUZZY_DATES, then "Truncated illegal value"
  is issued. This gives better warnings.

- Methods Type_handler::Item_get_date() and
  Type_handler::Item_func_hybrid_field_type_get_date() now only
  convert and collect warning information, but do not push warnings.

- Changing the return data type for Type_handler::Item_get_date()
  and Type_handler::Item_func_hybrid_field_type_get_date() from
  "bool" to "void". The conversion result (success vs error) can be
  checked by testing ltime->time_type. MYSQL_TIME_{NONE|ERROR}
  mean mean error, other values mean success.

- Adding new wrapper methods Type_handler::Item_get_date_with_warn() and
  Type_handler::Item_func_hybrid_field_type_get_date_with_warn()
  to do conversion followed by raising warnings, and changing
  the code to call new Type_handler::***_with_warn() methods.

- Adding a helper class Temporal::Status, a wrapper
  for MYSQL_TIME_STATUS with automatic initialization.

- Adding a helper class Temporal::Warn, to collect warnings
  but without actually raising them. Moving a part of ErrConv
  into a separate class ErrBuff, and deriving both Temporal::Warn
  and ErrConv from ErrBuff. The ErrBuff part of Temporal::Warn
  is used to collect textual representation of the input data.

- Adding a helper class Temporal::Warn_push. It's used
  to collect warning information during conversion, and
  automatically pushes warnings to the diagnostics area
  on its destructor time (in case of non-zero warning).

- Moving more code from various functions inside class Temporal.

- Adding more Temporal_hybrid constructors and
  protected Temporal methods make_from_xxx(),
  which convert and only collect warning information, but do not
  actually raise warnings.

- Now the low level functions  str_to_datetime() and str_to_time()
  always set status->warning if the return value is "true" (error).

- Now the low level functions number_to_time() and number_to_datetime()
  set the "*was_cut" argument if the return value is "true" (error).

- Adding a few DBUG_ASSERTs to make sure that str_to_xxx() and
  number_to_xxx() always set warnings on error.

- Adding new warning flags MYSQL_TIME_WARN_EDOM and MYSQL_TIME_WARN_ZERO_DATE
  for the code symmetry. Before this change there was a special
  code path for (rc==true && was_cut==0) which was treated by
  Field_temporal::store_invalid_with_warning as "zero date violation".
  Now was_cut==0 always means that there are no any error/warnings/notes
  to be raised, not matter what rc is.

- Using new Temporal_hybrid constructors in combination with
  Temporal::Warn_push inside str_to_datetime_with_warn(),
  double_to_datetime_with_warn(), int_to_datetime_with_warn(),
  Field::get_date(), Item::get_date_from_string(), and a few other places.

- Removing methods Dec_ptr::to_datetime_with_warn(),
  Year::to_time_with_warn(), my_decimal::to_datetime_with_warn(),
  Dec_ptr::to_datetime_with_warn().
  Fixing Sec6::to_time() and Sec6::to_datetime() to
  convert and only collect warnings, without raising warnings.
  Now warning raising functionality resides in Temporal::Warn_push.

- Adding classes Longlong_hybrid_null and Double_null, to
  return both value and the "IS NULL" flag. Adding methods
  Item::to_double_null(), to_longlong_hybrid_null(),
  Item_func_hybrid_field_type::to_longlong_hybrid_null_op(),
  Item_func_hybrid_field_type::to_double_null_op().
  Removing separate classes VInt and VInt_op, as they
  have been replaced by a single class Longlong_hybrid_null.

- Adding a helper method Temporal::type_name_by_timestamp_type(),
  moving a part of make_truncated_value_warning() into it,
  and reusing in Temporal::Warn::push_conversion_warnings().

- Removing Item::make_zero_date() and
  Item_func_hybrid_field_type::make_zero_mysql_time().
  They provided duplicate functionality.
  Now this code resides in Temporal::make_fuzzy_date().
  The latter is now called for all Item types when data type
  conversion (to DATE/TIME/DATETIME) is involved, including
  Item_field and Item_direct_view_ref.
  This fixes MDEV-17563: Item_direct_view_ref now correctly converts
  NULL to a zero date when TIME_FUZZY_DATES says so.
2018-11-08 09:31:46 +04:00
Alexander Barkov
b639fe2be1 MDEV-17351 Wrong results for GREATEST,TIMESTAMP,ADDTIME with an out-of-range TIME-alike argument
Problems:

Functions LEAST() and GREATEST() in TIME context, as well as functions
TIMESTAMP(a,b) and ADDTIME(a,b), returned confusing results when the
input TIME-alike value in a number or in a string was out of the TIME
supported range.

In case of TIMESTAMP(a,b) and ADDTIME(a,b), the second argument
value could get extra unexpected digits. For example, in:
    ADDTIME('2001-01-01 00:00:00', 10000000)  or
    ADDTIME('2001-01-01 00:00:00', '1000:00:00')
the second argument was converted to '838:59:59.999999'
with six fractional digits, which contradicted "decimals"
previously set to 0 in fix_length_and_dec().
These unexpected fractional digits led to confusing function results.

Changes:
1. GREATEST(), LEAST()

   - fixing Item_func_min_max::get_time_native()
   to respect "decimals" set by fix_length_and_dec().
   If a value of some numeric or string time-alike argument
   goes outside of the TIME range and gets limited to '838:59:59.999999',
   it's now right-truncated to the correct fractional precision.

   - fixing, Type_handler_temporal_result::Item_func_min_max_fix_attributes()
   to take into account arguments' time_precision() or datetime_precision(),
   rather than rely on "decimals" calculated by the generic implementation
   in Type_handler::Item_func_min_max_fix_attributes(). This makes
   GREATEST() and LEAST() return better data types, with the same
   fractional precision with what TIMESTAMP(a,b) and ADDTIME(a,b) return
   for the same arguments, and with DATE(a) and TIMESTAMP(a).

2. Item_func_add_time and Item_func_timestamp

   It was semantically wrong to apply the limit of the TIME data type
   to the argument "b", which plays the role of "INTERVAL DAY TO SECOND" here.
   Changing the code to fetch the argument "b" as INTERVAL rather than as TIME.

   The low level routine calc_time_diff() now gets the interval
   value without limiting to '838:59:59.999999', so in these examples:
     ADDTIME('2001-01-01 00:00:00', 10000000)
     ADDTIME('2001-01-01 00:00:00', '1000:00:00')
   calc_time_diff() gets '1000:00:00' as is.  The SQL function result
   now gets limited to the supported result data type range
   (datetime or time) inside calc_time_diff(), which now calculates
   the return value using the real fractional digits that
   came directly from the arguments (without the effect of limiting
   to the TIME range), so the result does not have any unexpected
   fractional digits any more.

   Detailed changes in TIMESTAMP() and ADDTIME():

   - Adding a new class Interval_DDhhmmssff. It's similar to Time, but:
     * does not try to parse datetime format, as it's not needed for
       functions TIMESTAMP() and ADDTIME().
     * does not cut values to '838:59:59.999999'

     The maximum supported Interval_DDhhmmssff's hard limit is
     'UINT_MAX32:59:59.999999'. The maximum used soft limit is:
     - '87649415:59:59.999999'   (in 'hh:mm:ss.ff' format)
     - '3652058 23:59:59.999999' (in 'DD hh:mm:ss.ff' format)
     which is a difference between:
     - TIMESTAMP'0001-01-01 00:00:00' and
     - TIMESTAMP'9999-12-31 23:59:59.999999'
     (the minimum datetime that supports arithmetic, and the
     maximum possible datetime value).

   - Fixing get_date() methods in the classes related to functions
     ADDTIME(a,b) and TIMESTAMP(a,b) to use the new class Interval_DDhhmmssff
     for fetching data from the second argument, instead of get_date().

   - Fixing fix_length_and_dec() methods in the classes related
     to functions ADDTIME(a,b) and TIMESTAMP(a,b) to use
     Interval_DDhhmmssff::fsp(item) instead of item->time_precision()
     to get the fractional precision of the second argument correctly.

   - Splitting the low level function str_to_time() into smaller pieces
     to reuse the code. Adding a new function str_to_DDhhmmssff(), to
     parse "INTERVAL DAY TO SECOND" values.

   After these changes, functions TIMESTAMP() and ADDTIME()
   return much more predictable results, in terms of fractional
   digits, and in terms of the overall result.

   The full ranges of DATETIME and TIME values are now covered by TIMESTAMP()
   and ADDTIME(), so the following can now be calculated:

    SELECT ADDTIME(TIMESTAMP'0001-01-01 00:00:00', '87649415:59:59.999999');
    -> '9999-12-31 23:59:59.999999'

    SELECT TIMESTAMP(DATE'0001-01-01', '87649415:59:59.999999')
    -> '9999-12-31 23:59:59.999999'

    SELECT ADDTIME(TIME'-838:59:59.999999', '1677:59:59.999998');
    -> '838:59:59.999999'
2018-10-08 13:38:01 +04:00
Michael Widenius
a7abddeffa Create 'main' test directory and move 't' and 'r' there 2018-03-29 13:59:44 +03:00
Renamed from mysql-test/r/func_sapdb.result (Browse further)