There are two databases: A.fdb and B.fdb.
You can think of A.fdb as the whole history database up to yesterday and B.fdb as today's database.
I need to merge B.fdb into A.fdb.
[1] Update or insert records from B.fdb's I2 into A.fdb's I2
[2] Update or insert records from B.fdb's A2 into A.fdb's A2
[3] Update or insert records from B.fdb's D2 into A.fdb's D2

I am trying to do these using Procedure Merge as shown below.
Not sure how to handle two databases at the same time.
I need some help on completing this procedure.

thx
HR

<Database A.fdb>

create table I2
(
ID integer not null primary key,
INST varchar(32) not null unique
);

create table A2
(
ALI varchar(32) not null unique,
ID integer not null references I2(ID) on update cascade on delete cascade
);

create table D2
(
ID integer not null,
YMD date not null,
TB integer,
MB integer,
DB integer,
primary key(ID, YMD),
foreign key(ID) references I2(ID) on update cascade on delete cascade
);

create sequence SeqInst;

set term ^ ;
create trigger trg_I2_BI_P0 for i2
active before insert position 0
as
begin
if ((new.id is null) or (new.id = 0)) then
begin
new.id = gen_id(SeqInst, 1);
end
end
^
set term ; ^


<Database B.fdb>

create table I2
(
ID integer not null primary key,
INST varchar(32) not null unique
);

create table A2
(
ALI varchar(32) not null unique,
ID integer not null references I2(ID) on update cascade on delete cascade
);


create table D2
(
ID integer not null,
YMD date not null,
TB integer,
MB integer,
DB integer,
primary key(ID, YMD),
foreign key(ID) references I2(ID) on update cascade on delete cascade
);

create sequence SeqInst;

set term ^ ;
create trigger trg_I2_BI_P0 for i2
active before insert position 0
as
begin
if ((new.id is null) or (new.id = 0)) then
begin
new.id = gen_id(SeqInst, 1);
end
end
^
set term ; ^


set term ^ ;

CREATE PROCEDURE MERGE(DB1 VARCHAR(256), DB1 VARCHAR(256))
AS
DECLARE VARIABLE ID INTEGER;
BEGIN
CONNECT :DB1 AS DB_1 USER 'SYSDBA' PASSWORD 'MASTERKEY';
CONNECT :DB2 AS DB_2 USER 'SYSDBA' PASSWORD 'MASTERKEY';

/* [1] */
...

/* [2] */
...

/* [3] */
...

END
^

set term ; ^