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#222 filter out degenerate key range in tokudb::record_in_range

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This commit is contained in:
Rich Prohaska 2014-04-30 18:19:14 -04:00
parent 1a58d90e41
commit 0a75992219
1 changed files with 24 additions and 45 deletions
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69
storage/tokudb/ha_tokudb.cc
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@ -7329,23 +7329,18 @@ double ha_tokudb::index_only_read_time(uint keynr, double records) {
//
ha_rows ha_tokudb::records_in_range(uint keynr, key_range* start_key, key_range* end_key) {
TOKUDB_HANDLER_DBUG_ENTER("");
DBT *pleft_key = NULL, *pright_key = NULL;
DBT *pleft_key, *pright_key;
DBT left_key, right_key;
ha_rows ret_val = HA_TOKUDB_RANGE_COUNT;
DB *kfile = share->key_file[keynr];
uint64_t less, equal1, middle, equal2, greater;
uint64_t rows;
bool is_exact;
uint64_t rows = 0;
int error;
uchar inf_byte;
//
// get start_rows and end_rows values so that we can estimate range
// when calling key_range64, the only value we can trust is the value for less
// The reason is that the key being passed in may be a prefix of keys in the DB
// As a result, equal may be 0 and greater may actually be equal+greater
// So, we call key_range64 on the key, and the key that is after it.
//
if (!start_key && !end_key) {
error = estimate_num_rows(kfile, &rows, transaction);
if (error) {
@ -7356,54 +7351,38 @@ ha_rows ha_tokudb::records_in_range(uint keynr, key_range* start_key, key_range*
goto cleanup;
}
if (start_key) {
inf_byte = (start_key->flag == HA_READ_KEY_EXACT) ?
COL_NEG_INF : COL_POS_INF;
pack_key(
&left_key,
keynr,
key_buff,
start_key->key,
start_key->length,
inf_byte
);
uchar inf_byte = (start_key->flag == HA_READ_KEY_EXACT) ? COL_NEG_INF : COL_POS_INF;
pack_key(&left_key, keynr, key_buff, start_key->key, start_key->length, inf_byte);
pleft_key = &left_key;
} else {
pleft_key = NULL;
}
if (end_key) {
inf_byte = (end_key->flag == HA_READ_BEFORE_KEY) ?
COL_NEG_INF : COL_POS_INF;
pack_key(
&right_key,
keynr,
key_buff2,
end_key->key,
end_key->length,
inf_byte
);
uchar inf_byte = (end_key->flag == HA_READ_BEFORE_KEY) ? COL_NEG_INF : COL_POS_INF;
pack_key(&right_key, keynr, key_buff2, end_key->key, end_key->length, inf_byte);
pright_key = &right_key;
} else {
pright_key = NULL;
}
error = kfile->keys_range64(
kfile,
transaction,
pleft_key,
pright_key,
&less,
&equal1,
&middle,
&equal2,
&greater,
&is_exact
);
if (error) {
ret_val = HA_TOKUDB_RANGE_COUNT;
goto cleanup;
// keys_range64 can not handle a degenerate range (left_key > right_key), so we filter here
if (pleft_key && pright_key && tokudb_cmp_dbt_key(kfile, pleft_key, pright_key) > 0) {
rows = 0;
} else {
uint64_t less, equal1, middle, equal2, greater;
bool is_exact;
error = kfile->keys_range64(kfile, transaction, pleft_key, pright_key,
&less, &equal1, &middle, &equal2, &greater, &is_exact);
if (error) {
ret_val = HA_TOKUDB_RANGE_COUNT;
goto cleanup;
}
rows = middle;
}
rows = middle;
//
// MySQL thinks a return value of 0 means there are exactly 0 rows
// Therefore, always return non-zero so this assumption is not made
//
ret_val = (ha_rows) (rows <= 1 ? 1 : rows);
cleanup:
DBUG_RETURN(ret_val);
}