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compatibility fixes

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This commit is contained in:
serg@serg.mylan
2004-11-29 22:47:50 +01:00
parent 5ce151891a
commit ceb0d1cf87
8 changed files with 36 additions and 28 deletions
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15
sql/sql_select.cc
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@ -3464,7 +3464,7 @@ best_access_path(JOIN *join,
{
/*
Assume that the first key part matches 1% of the file
and that the hole key matches 10 (duplicates) or 1
and that the whole key matches 10 (duplicates) or 1
(unique) records.
Assume also that more key matches proportionally more
records
@ -3472,7 +3472,7 @@ best_access_path(JOIN *join,
records = (x * (b-a) + a*c-b)/(c-1)
b = records matched by whole key
a = records matched by first key part (10% of all records?)
a = records matched by first key part (1% of all records?)
c = number of key parts in key
x = used key parts (1 <= x <= c)
*/
@ -3488,9 +3488,12 @@ best_access_path(JOIN *join,
else
{
double a=s->records*0.01;
tmp = (max_key_part * (rec_per_key - a) +
a*keyinfo->key_parts - rec_per_key)/
(keyinfo->key_parts-1);
if (keyinfo->key_parts > 1)
tmp= (max_key_part * (rec_per_key - a) +
a*keyinfo->key_parts - rec_per_key)/
(keyinfo->key_parts-1);
else
tmp= a;
set_if_bigger(tmp,1.0);
}
records = (ulong) tmp;
@ -4421,7 +4424,7 @@ 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 (duplicates) or 1
and that the whole key matches 10 (duplicates) or 1
(unique) records.
Assume also that more key matches proportionally more
records