Copy fields from one column to another with criteria - sql

Question

I have a table called 02_Month with the following information:
|------------------------------------------------------------------
| Soc | Society | USD_STD | USD_STD_R |
|------------------------------------------------------------------|
| AB02 | Plants | 3.8 | 1 |
| JK01 | Trees | 2.4 | 1 |
| WB09 | Bushes | 1.2 | 3 |
| COIN | Flowers | 4.6 | 2 |
| KK99 | Stones | 66.9 | 3 |
| TCTC | Ruby | 19.0 | 5 |
| WNOL | Steel | 71.1 | 7 |
|------------------------------------------------------------------
I want to copy what says in column USD_STD to USD_STD_R if the column Soc is COIN or TCTC. I want to have this at the end:
|------------------------------------------------------------------
| Soc | Society | USD_STD | USD_STD_R |
|------------------------------------------------------------------|
| AB02 | Plants | 3.8 | 1 |
| JK01 | Trees | 2.4 | 1 |
| WB09 | Bushes | 1.2 | 3 |
| COIN | Flowers | 4.6 | 4.6 |
| KK99 | Stones | 66.9 | 3 |
| TCTC | Ruby | 19.0 | 19.0 |
| WNOL | Steel | 71.1 | 7 |
|------------------------------------------------------------------
I wrote this:
UPDATE 02_Month
SET [02_Month].USD_STD_R = USD_STD
WHERE (([02_Month].Soc="COIN") or ([02_Month].Soc="TCTC"));
It is not working as expected. I suppose it's due to the WHERE condition. if I don't write that line it copies the entire column USD_STD in USD_STD_R.
The code I wrote prints 0 in all of the fields of USD_STD_R. Why doesn't it work and how can it be corrected?

Answer 1

The following should be sufficient:
update [02_month] t
set t.usd_std_r = t.usd_std
where t.soc="COIN" or t.soc="TCTC"
A few notes:
Since your table name starts with a number, it must be enclosed in square brackets.
The use of t is merely an alias to avoid the need to repeatedly write [02_month]
You can use either t.soc="COIN" or t.soc="TCTC" or t.soc in ("COIN","TCTC") both should yield the same result.
Double-quotes " are typically used by MS Access, but single-quotes ' should also be valid.

Answer 2

USD_STD instead of STD_USD
Also you can use IN operator
UPDATE 02_Month
SET [02_Month].USD_STD_R = USD_STD
FROM [02_Month]
WHERE ([02_Month].Soc IN ('COIN','TCTC'));

Answer 3

Please, try with below query. string value always within ''.
UPDATE 02_Month
SET USD_STD_R = USD_STD
WHERE Soc in ('COIN','TCTC');

Answer 4

your relation 02_month with column field USD_STD USD_STD_R but in update statement column field name is STD_USD_R and STD_USD.

Answer 5

You can use inner join update as shown below.
UPDATE a
SET a.USD_STD_R = b.USD_STD --You can change another column here as per your need.
FROM [02_Month] a
INNER JOIN [02_Month] b ON a.soc = b.soc
AND a.society = b.society
AND a.USD_STD = b.USD_STD
AND a.USD_STD_R = b.USD_STD_R
WHERE a.Soc in ('COIN','TCTC');
Live Demo Here
If you do not want alias name for updating table.
UPDATE [02_Month]
SET [02_Month].USD_STD_R = b.USD_STD --You can change another column here as per your need.
FROM [02_Month]
INNER JOIN [02_Month] b ON [02_Month].soc = b.soc
AND [02_Month].society = b.society
AND [02_Month].USD_STD = b.USD_STD
AND [02_Month].USD_STD_R = b.USD_STD_R
WHERE [02_Month].Soc in ('COIN','TCTC');
db<>fiddle Demo