What I am trying to do. I want to confirm that IvanIvanov from column A corresponds to IvanIvanov _32_y1988_12 from column B. I do not know how to extract IvanIvanov from column B and to compare it with column A. I have tried several things but unsuccessfully.
Then I want to compare column C y1988_12 with part of column B IvanIvanov_32_ y1988_12 .
DBMS MariaDB
Thank you in advance for the help.
Table representation:
A | B | C |
---|---|---|
IvanIvanov | IvanIvanov_32_y1988_12 | y1988_12 |
You wonder how to extract the two substrings from B. You don't have to. You merely want to know whether B starts or ends with the substrings A and C. The easiest aproach here is probably LIKE
. I am assuming your DBMS is MySQL or MariaDB for the mentioned function SUBSTRING_INDEX
.
With MySQL's CONCAT
function:
select
b like concat(a, '%') as b_starts_with_a,
b like concat('%', c) as b_ends_with_c
from mytable;
Or with the standard SQL concatenation operator:
select
b like a || '%' as b_starts_with_a,
b like '%' || c as b_ends_with_c
from mytable;
This gives you true / 1 in case of a match and false / 0 in case of a mismatch
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