连接两列中的值，并将其与sqlite中的一个值进行比较

Question

I am using sqlite in one my ios project where among other columns there are two columns. one has country code for mobile dialing like +880 and other column has rest of the mobile number like 1912353697. Now i want to join values from these two columns and compare the result value against like +8801912353697 and if matches pull the corresponding name value in that table . what would be the right query. I have tried like SELECT name FROM CONTACT_LIST WHERE (SELECT mblDc || mbl FROM CONTACT_LIST) = "+8801617634317" ; but that does not work .

A help would be appreciated.

Answer 1

Try:

SELECT name FROM CONTACT_LIST 
WHERE mblDc || mbl = "+8801617634317";

From SQLite documentation : The || operator is "concatenate" - it joins together the two strings of its operands. The || operator is "concatenate" - it joins together the two strings of its operands.

Answer 2

please check How to concatenate strings with padding in sqlite

using substr function we can do the job and the query should be like

SELECT name FROM CONTACT_LIST WHERE  (mblDc || mbl) = "+8801617634317" ;