HANDLER for MEMORY Tables
If you want to scan a table for over different key values, not just search for exact key values, you should create your keys with 'USING BTREE':
CREATE TABLE t1 (a INT, b INT, KEY(a), KEY b USING BTREE (b)) engine=memory;
The limitations for HANDLER READ with Memory|HEAP tables are:
Limitations for HASH keys
- You must use all key parts when searching for a row.
- You can't do a key scan of all values. You can only find all rows with the same key value.
- READ NEXT gives error 1031 if the tables changed since last read.
Limitations for BTREE keys
- READ NEXT gives error 1031 if the tables changed since last read. This limitation can be lifted in the future.
Limitations for table scans
- READ NEXT gives error 1031 if the table was truncated since last READ call.
See also the the limitations listed in HANDLER commands.