HR wrote
<<
...
The previous database design was
- multiple yearly databases
- three tables
- single key having symb and date combined
- no indexing

The new database will be
[1] One single database file : OneBigDB.fdb
[2] One single table : DAILYBLOB
[3] Five columns : SYMB, YMD, TB, MB, DB
[4] Primary keys : SYMB, YMD
[5] Index : YMD (descending)

CREATE TABLE DAILYBLOB
(
SYMB VARCHAR(20) NOT NULL,
YMD DATE NOT NULL,
TB BLOB SUBTYPE BINARY,
MB BLOB SUBTYPE BINARY,
DB BLOB SUBTYPE BINARY,
PRIMARY KEY(SYMB, YMD)
);

CREATE DESC INDEX YMD_IDX ON DAILYBLOB(YMD);
...

>>

Maybe two tables will be better?
create table DAILYMAIN (
ID integer not null primary key,
SYMB varchar(20) not null,
YMD date not null
);
create table DAILYBLOB (
ID integer not null primary key,
TB blob ...,
MB blob ...,
DB blob ...
);
Individual indexes on SYMB and YMD (whatever proves beneficial).
These tables are in a one-to-one relationship (on their IDs, use a
single generator).

Keeping blobs outside of the "main" table might make for more
efficient search and retrieval (if you don't always need the blobs). YMMV.

--
Aage J.