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MDEV-16188: Use in-memory PK filters built from range index scans

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First phase: make optimizer choose to use filter and show it in EXPLAIN.
This commit is contained in:
Galina Shalygina
2018-08-16 00:24:52 +03:00
parent befc09f002
commit 8d5a11122c
17 changed files with 722 additions and 18 deletions
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23
sql/handler.cc
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@@ -2601,6 +2601,22 @@ LEX_CSTRING *handler::engine_name()
}
/**
The method returns the cost of the random I/O accesses when
index is used.
*/
double handler::get_io_cost(uint index, ha_rows rows, uint *length)
{
uint len= table->key_info[index].key_length + ref_length;
if (index == table->s->primary_key && table->file->primary_key_is_clustered())
len= table->s->stored_rec_length;
double keys_per_block= (stats.block_size/2.0/len+1);
*length= len;
return (rows + keys_per_block-1)/ keys_per_block;
}
double handler::keyread_time(uint index, uint ranges, ha_rows rows)
{
/*
@@ -2612,11 +2628,8 @@ double handler::keyread_time(uint index, uint ranges, ha_rows rows)
engines that support that (e.g. InnoDB) may want to overwrite this method.
The model counts in the time to read index entries from cache.
*/
size_t len= table->key_info[index].key_length + ref_length;
if (index == table->s->primary_key && table->file->primary_key_is_clustered())
len= table->s->stored_rec_length;
double keys_per_block= (stats.block_size/2.0/len+1);
return (rows + keys_per_block-1)/ keys_per_block +
uint len;
return get_io_cost(index, rows, &len) +
len*rows/(stats.block_size+1)/TIME_FOR_COMPARE ;
}