Hi, Nikita!

On Jan 31, Nikita Malyavin wrote:
> revision-id: b1a4d1e4937 (versioning-1.0.7-3-gb1a4d1e4937)
> parent(s): 4b01d3aee60
> author: Nikita Malyavin <nikitamalyavin@gmail.com>
> committer: Nikita Malyavin <nikitamalyavin@gmail.com>
> timestamp: 2019-01-30 22:54:00 +1000
> message:
>
> MDEV-16973 Application-time periods: DELETE
>
> * inject portion of time updates into mysql_delete main loop
> * triggered case emits delete+insert, no updates
> * PORTION OF `SYSTEM_TIME` is forbidden
> * `DELETE HISTORY .. FOR PORTION OF ...` is forbidden as well

> diff --git a/mysql-test/suite/period/r/delete.result b/mysql-test/suite/period/r/delete.result
> --- /dev/null
> +++ b/mysql-test/suite/period/r/delete.result
> @@ -0,0 +1,244 @@
> +create or replace table t (id int, s date, e date, period for apptime(s,e));
> +insert into t values(1, '1999-01-01', '2018-12-12');
> +insert into t values(1, '1999-01-01', '2017-01-01');
> +insert into t values(1, '2017-01-01', '2019-01-01');
> +insert into t values(2, '1998-01-01', '2018-12-12');
> +insert into t values(3, '1997-01-01', '2015-01-01');
> +insert into t values(4, '2016-01-01', '2020-01-01');
> +insert into t values(5, '2010-01-01', '2015-01-01');
> +create or replace table t1 (id int, s date, e date, period for apptime(s,e));
> +insert t1 select * from t;
> +create or replace table t2 (id int, s date, e date, period for apptime(s,e));
> +insert t2 select * from t;
> +delete from t for portion of apptime from '2000-01-01' to '2018-01-01';
> +delete from t1 for portion of APPTIME from '2000-01-01' to '2018-01-01';
> +select * from t;
> +id   s       e
> +1    1999-01-01      2000-01-01
> +1    1999-01-01      2000-01-01
> +1    2018-01-01      2018-12-12
> +1    2018-01-01      2019-01-01
> +2    1998-01-01      2000-01-01
> +2    2018-01-01      2018-12-12
> +3    1997-01-01      2000-01-01
> +4    2018-01-01      2020-01-01
> +select * from t1;
> +id   s       e
> +1    1999-01-01      2000-01-01
> +1    1999-01-01      2000-01-01
> +1    2018-01-01      2018-12-12
> +1    2018-01-01      2019-01-01
> +2    1998-01-01      2000-01-01
> +2    2018-01-01      2018-12-12
> +3    1997-01-01      2000-01-01
> +4    2018-01-01      2020-01-01
> +select * from log_tbl;
> +id   log

here (and everywhere selecting from log_tbl), better do ORDER BY id
it's quite difficult to follow the sequence of events otherwise

> +# auto_increment field overflow
> +create or replace table t (id tinyint auto_increment primary key,
> +s date, e date, period for apptime(s,e));
> +insert into t values(127, '1999-01-01', '2018-12-12');
> +delete from t for portion of apptime from '2000-01-01' to '2018-01-01';
> +ERROR 22003: Out of range value for column 'id' at row 1

add select * from t here, please

> +# same for trigger case
> +delete from t for portion of apptime from '2000-01-01' to '2018-01-01';
> +ERROR 22003: Out of range value for column 'id' at row 1

and here
and select from the log_tbl too

> diff --git a/mysql-test/suite/versioning/t/select.test b/mysql-test/suite/versioning/t/select.test
> --- a/mysql-test/suite/versioning/t/select.test
> +++ b/mysql-test/suite/versioning/t/select.test
> @@ -107,6 +107,32 @@ for system_time as of timestamp @t0 as t;
>  drop table t1;
>  drop table t2;
> 
> +# Query conditions check
> +
> +create or replace table t1(x int) with system versioning;
> +insert into t1 values (1);
> +delete from t1;
> +insert into t1 values (2);
> +delete from t1;
> +insert into t1 values (3);
> +delete from t1;
> +
> +select row_start into @start1 from t1 for system_time all where x = 1;
> +select row_end into @end1 from t1 for system_time all where x = 1;
> +select row_start into @start2 from t1 for system_time all where x = 2;
> +select row_end into @end2 from t1 for system_time all where x = 2;
> +select row_start into @start3 from t1 for system_time all where x = 3;
> +select row_end into @end3 from t1 for system_time all where x = 3;
> +
> +select x as ASOF_x from t1 for system_time as of @start2;
> +select x as ASOF_x from t1 for system_time as of @end2;
> +select x as FROMTO_x from t1 for system_time from @start1 to @end3;
> +select x as FROMTO_x from t1 for system_time from @end1 to @start2;
> +select x as BETWAND_x from t1 for system_time between @start1 and @end3;
> +select x as BETWAND_x from t1 for system_time between @end1 and @start2;
> +
> +drop table t1;

what does that have to do with MDEV-16973?

> > > +      || unique_table(thd, table_list, table_list->next_global, 0))
> > >      *delete_while_scanning= false;
> > >
> 
> > > +    case SYSTEM_TIME_FROM_TO:
> > > +      cond1= newx Item_func_trt_trx_sees(thd, trx_id1, conds.field_start);
> > > +      cond3= newx Item_func_lt(thd, conds.start.item, conds.end.item);
> > > +      break;
> >
> > hmm, you don't use trx_id0 here at all. did you forget
> >
> >   cond2= newx Item_func_trt_trx_sees_eq(thd, conds.field_end, trx_id0);
> >
> yes, looks so... The tests did not catch this
add a new test, perhaps? :)

> +
>  # Wildcard expansion on hidden fields
> 
>  create table t1(
> @@ -233,9 +259,9 @@ select x from t1 for system_time as of @trx_start;
>  --echo ### Issue #365, bug 4 (related to #226, optimized fields)
>  create or replace table t1 (i int, b int) with system versioning;
>  insert into t1 values (0, 0), (0, 0);
> -select min(i) over (partition by b) as f
> -from (select i + 0 as i, b from t1) as tt
> -order by i;
> +#select min(i) over (partition by b) as f
> +#from (select i + 0 as i, b from t1) as tt
> +#order by i;

why is this?

> diff --git a/sql/sql_delete.cc b/sql/sql_delete.cc
> --- a/sql/sql_delete.cc
> +++ b/sql/sql_delete.cc
> @@ -245,6 +245,48 @@ static bool record_should_be_deleted(THD *thd, TABLE *table, SQL_SELECT *sel,
>    return false;
>  }
> 
> +inline
> +int TABLE::update_portion_of_time(THD *thd,
> +                                  const vers_select_conds_t &period_conds,
> +                                  bool *inside_period)

I don't understand why you want to keep this very much DELETE-only
functionality in the TABLE class which is used everywhere.

And what's the point of pretending it's in a common TABLE class,
if it can only be used in sql_delete.cc? I find it quite confusing :(

>  inline
>  int TABLE::delete_row()
> @@ -672,6 +736,9 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds,
> 
>    table->mark_columns_needed_for_delete();
> 
> +  if (table_list->has_period())
> +    table->use_all_columns();

may be even

  if (table_list->has_period())
    table->use_all_columns()
  else
    table->mark_columns_needed_for_delete();

> +
>    if ((table->file->ha_table_flags() & HA_CAN_FORCE_BULK_DELETE) &&
>        !table->prepare_triggers_for_delete_stmt_or_event())
>      will_batch= !table->file->start_bulk_delete();
> @@ -727,6 +794,16 @@ bool mysql_delete(THD *thd, TABLE_LIST *table_list, COND *conds,
>      delete_record= true;
>    }
> 
> +  /*
> +    From SQL2016, Part 2, 15.7 <Effect of deleting rows from base table>,
> +    General Rules, 8), we can conclude that DELETE FOR PORTTION OF time performs
> +    0-2 INSERTS + DELETE. We can substitute INSERT+DELETE with one UPDATE, but
> +    only if there are no triggers set.
> +    It is also meaningless for system-versioned table
> +  */
> +  portion_of_time_through_update= !has_triggers
> +                               && !table->versioned(VERS_TIMESTAMP);

I still don't understand why you disable portion_of_time_through_update
for VERS_TIMESTAMP, but not for VERS_TRX_ID.

> +
>    THD_STAGE_INFO(thd, stage_updating);
>    while (likely(!(error=info.read_record())) && likely(!thd->killed) &&
>           likely(!thd->is_error()))
> diff --git a/sql/sql_lex.cc b/sql/sql_lex.cc
> --- a/sql/sql_lex.cc
> +++ b/sql/sql_lex.cc
> @@ -3576,6 +3577,20 @@ void LEX::set_trg_event_type_for_tables()
>      break;
>    }
> 
> +  if (period_conditions.is_set())
> +  {
> +    switch (sql_command)
> +    {
> +    case SQLCOM_DELETE:
> +    case SQLCOM_UPDATE:
> +    case SQLCOM_REPLACE:
> +      new_trg_event_map |= static_cast<uint8>
> +                             (1 << static_cast<int>(TRG_EVENT_INSERT));

I've added a helper for this recently, use

     new_trg_event_map |= trg2bit(TRG_EVENT_INSERT);

> +    default:
> +      break;
> +    }
> +  }
> +
> 
>    /*
>      Do not iterate over sub-selects, only the tables in the outermost
> diff --git a/sql/sql_yacc.yy b/sql/sql_yacc.yy
> --- a/sql/sql_yacc.yy
> +++ b/sql/sql_yacc.yy
> @@ -9295,6 +9296,22 @@ history_point:
>              $$= Vers_history_point($1, $2);
>            }
>          ;
> +opt_for_portion_of_time_clause:
> +          /* empty */
> +          {
> +            $$= false;
> +          }
> +        | FOR_SYM PORTION_SYM OF_SYM ident FROM history_point TO_SYM history_point

history_point allows TIMESTAMP '2010-10-10 10:10:10' and
TRANSACTION 1234.

You don't need any of that, just use a corresponding expression
rule. E.g. bit_expr, like history_point does.

> +          {
> +            if (unlikely(0 == strcasecmp($4.str, "SYSTEM_TIME")))
> +            {
> +              thd->parse_error(ER_SYNTAX_ERROR, $4.str);

no, for the error message to look correct you need to pass the pointer
into the query text. It's usually done like this:

      FOR_SYM PORTION_SYM OF_SYM remember_tok_start ident FROM ...
      {
         ...
         thd->parse_error(ER_SYNTAX_ERROR, $4);