[COLOR="Blue"]id debtor debtorBalance amount creditor creditorBalance[/COLOR]
I have 6 columns like the above.
(1) I invest 100 dollars to my company in cash
I like to save transaction (1) like the below.
[COLOR="Blue"]id debtor debtorBalance amount creditor creditorBalance[/COLOR]
(1) cash [COLOR="Red"]100[/COLOR] 100 capital [COLOR="Red"]100[/COLOR]
Because there is no cash before transaction (1),
the value of $pre_cash is 0,
So the debtor balance (cash balance) is 100 which is 100 (this transction) + 0 ($pre_cash).
Because there is no capital before transaction (1),
the value of $pre_capital is 0,
So the creditor balance (capital balance) is 100 which is 100 (this transction) + 0 ($pre_capital).
(2) I save 60 dollars of the company cash to bank.
I like to save the transaction (2) like the below.
[COLOR="Blue"]id debtor debtorBalance amount creditor creditorBalance[/COLOR]
(1) cash 100 100 capital 100
(2) bank 60 [COLOR="Red"]60[/COLOR] cash [SIZE="5"][COLOR="Red"]40[/COLOR][/SIZE]
Because there is no bank before transaction (2),
the value of $pre_bank is 0,
So the creditor balance (bank balance) is 60 which is 60 ($this transction) - 0 (pre_bank).
Because pre_cash in the transaction (1) is 100 before transaction (2),
the value of $pre_cash is 100,
So the creditor balance (cash balance) is 40 which is 100(pre_cash) - 60 ($this transction).
The main question of mine in this post is how I call $pre_cash for saving cash balance.
For calling $pre_cash, I try to think that I have to find the last record(ORDER BY ID DESC LIMIT 1) which has
cash in “debtor” (WHERE DEBTOR=‘cash’) or(UNION) creditor(WHERE CREDITOR=‘cash’).
The trial code below doesn’t work correctly but I hope it shows what I want.
[b]trial code[/b]
( select debtorBalance as preBalance from accountLog
where debtor = 'cash'
UNION
select creditorBalance as preBalance from accountLog
where creditor = 'cash')
order by id desc limit 1