从两列中选择值并将它们串联到另一张表的一列中

Question

I'm a bit new to SQL and trying to do what my description above says. This below is my query:

SELECT
     CONCAT (first_name, last_name) INTO full_name_variable
FROM
    table_1
WHERE
    phone_number = new.number;

It doesn't seem to work. However, when I use this query using AS it works. Like this:

SELECT
      CONCAT (first_name, last_name) AS full_name_variable
FROM
      table_1
WHERE
    phone_number = new.number;

I'd really appreciate the help

Answer 1

Use explicitly join instead

SELECT CONCAT (first_name, last_name) INTO full_name_variable
FROM table_1 t1
INNER JOIN tabke_2 t1 
       ON t1.phone_number = t2.number;

Or you may use INSRET INTO statement

INSERT INTO full_name_variable (full_name)
SELECT CONCAT (first_name, last_name) 
FROM table_1 t1
INNER JOIN tabke_2 t1 
      ON t1.phone_number = t2.number;

Answer 2

You need to learn the difference between a variable and a column .

INTO loads the value into a variable, that is available in the programming block you are using. It is the same a := . So your first version is the same as:

SELECT full_name_variable := CONCAT(first_name, last_name)
FROM table_1
WHERE phone_number = new.number;

AS (which is actually optional), names a column in a result set.

Your code appears to be in a trigger where one does not normally return a result set. My guess is that you want INTO or := . I prefer := because I find it more intuitive for setting variables.