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merge changes

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This commit is contained in:
Sinisa@sinisa.nasamreza.org
2003-07-02 00:26:23 +03:00
parent c1660e1a23 65a36828c8
commit b7644c9212
99 changed files with 4208 additions and 276 deletions
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43
sql/sql_select.cc
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@ -1277,14 +1277,14 @@ make_join_statistics(JOIN *join,TABLE_LIST *tables,COND *conds,
/*
Set a max range of how many seeks we can expect when using keys
This was (s->read_time*5), but this was too low with small rows
This is can't be to high as otherwise we are likely to use
table scan.
*/
s->worst_seeks= (double) s->found_records / 5;
s->worst_seeks= min((double) s->found_records / 10,
(double) s->read_time*3);
if (s->worst_seeks < 2.0) // Fix for small tables
s->worst_seeks=2.0;
/* if (s->type == JT_EQ_REF)
continue; */
if (s->const_keys)
{
ha_rows records;
@ -1890,6 +1890,7 @@ find_best(JOIN *join,table_map rest_tables,uint idx,double record_count,
best=best_time=records=DBL_MAX;
KEYUSE *best_key=0;
uint best_max_key_part=0;
my_bool found_constrain= 0;
if (s->keyuse)
{ /* Use key if possible */
@ -1970,6 +1971,7 @@ find_best(JOIN *join,table_map rest_tables,uint idx,double record_count,
}
else
{
found_constrain= 1;
/*
Check if we found full key
*/
@ -2006,16 +2008,18 @@ find_best(JOIN *join,table_map rest_tables,uint idx,double record_count,
records=2.0; // Can't be as good as a unique
}
}
/* Limit the number of matched rows */
tmp= records;
set_if_smaller(tmp, (double) thd->variables.max_seeks_for_key);
if (table->used_keys & ((key_map) 1 << key))
{
/* we can use only index tree */
uint keys_per_block= table->file->block_size/2/
(keyinfo->key_length+table->file->ref_length)+1;
tmp=(record_count*(records+keys_per_block-1)/
keys_per_block);
tmp=record_count*(tmp+keys_per_block-1)/keys_per_block;
}
else
tmp=record_count*min(records,s->worst_seeks);
tmp=record_count*min(tmp,s->worst_seeks);
}
}
else
@ -2045,7 +2049,7 @@ find_best(JOIN *join,table_map rest_tables,uint idx,double record_count,
{
/*
Assume that the first key part matches 1% of the file
and that the hole key matches 10 (dupplicates) or 1
and that the hole key matches 10 (duplicates) or 1
(unique) records.
Assume also that more key matches proportionally more
records
@ -2077,6 +2081,8 @@ find_best(JOIN *join,table_map rest_tables,uint idx,double record_count,
records=(ulong) tmp;
}
}
/* Limit the number of matched rows */
set_if_smaller(tmp, (double) thd->variables.max_seeks_for_key);
if (table->used_keys & ((key_map) 1 << key))
{
/* we can use only index tree */
@ -2119,20 +2125,31 @@ find_best(JOIN *join,table_map rest_tables,uint idx,double record_count,
s->table->used_keys && best_key) &&
!(s->table->force_index && best_key))
{ // Check full join
ha_rows rnd_records= s->found_records;
if (s->on_expr)
{
tmp=rows2double(s->found_records); // Can't use read cache
tmp=rows2double(rnd_records); // Can't use read cache
}
else
{
tmp=(double) s->read_time;
/* Calculate time to read through cache */
/* Calculate time to read previous rows through cache */
tmp*=(1.0+floor((double) cache_record_length(join,idx)*
record_count /
(double) thd->variables.join_buff_size));
}
/*
If there is a restriction on the table, assume that 25% of the
rows can be skipped on next part.
This is to force tables that this table depends on before this
table
*/
if (found_constrain)
rnd_records-= rnd_records/4;
if (best == DBL_MAX ||
(tmp + record_count/(double) TIME_FOR_COMPARE*s->found_records <
(tmp + record_count/(double) TIME_FOR_COMPARE*rnd_records <
best + record_count/(double) TIME_FOR_COMPARE*records))
{
/*
@ -2140,7 +2157,7 @@ find_best(JOIN *join,table_map rest_tables,uint idx,double record_count,
will ensure that this will be used
*/
best=tmp;
records= rows2double(s->found_records);
records= rows2double(rnd_records);
best_key=0;
}
}
@ -5947,6 +5964,8 @@ create_sort_index(JOIN_TAB *tab, ORDER *order, ha_rows filesort_limit,
/*
We have a ref on a const; Change this to a range that filesort
can use.
For impossible ranges (like when doing a lookup on NULL on a NOT NULL
field, quick will contain an empty record set.
*/
if (!(select->quick=get_ft_or_quick_select_for_ref(table, tab)))
goto err;