Question

Here is my example. When I run this query:

SELECT SUBSTRING('Lorem ipsum dolor sit amet, consectetur adipiscing elit. Donec vitae odio tellus, sit amet facilisis neque. Cras sapien nulla, suscipit non imperdiet ac, aliquet vitae lectus. Nulla a varius dolor. Nunc convallis, augue et fermentum volutpat, lectus urna sagittis risus, vel iaculis diam est convallis lectus. Suspendisse potenti. Morbi malesuada tristique varius.', 1, 300)

I get the first 300 chars of the sentence. That is good. Except that I want it to end where the last dot (.) is in the result.

So the query result is this:

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Donec vitae odio tellus, sit amet facilisis neque. Cras sapien nulla, suscipit non imperdiet ac, aliquet vitae lectus. Nulla a varius dolor. Nunc convallis, augue et fermentum volutpat, lectus urna sagittis risus, vel iaculis diam est convalli

But I want it to be this:

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Donec vitae odio tellus, sit amet facilisis neque. Cras sapien nulla, suscipit non imperdiet ac, aliquet vitae lectus. Nulla a varius dolor.

Can I do that with a MySQL query, and how?

Tnx

---

UPDATE 1,
This is what I had so far:

SET @longtext = 'Lorem ipsum dolor sit amet, consectetur adipiscing elit. Donec vitae odio tellus, sit amet facilisis neque. Cras sapien nulla, suscipit non imperdiet ac, aliquet vitae lectus. Nulla a varius dolor. Nunc convallis, augue et fermentum volutpat, lectus urna sagittis risus, vel iaculis diam est convallis lectus. Suspendisse potenti. Morbi malesuada tristique varius.';

SELECT SUBSTRING_INDEX(
    @longtext,
    SUBSTRING_INDEX(
        SUBSTRING(
            @longtext,
            1,
            300
        ),
        '.',
        -1
    )
    , 1
);

---

UPDATE 2,
Tnx @Ben

My solution is:

SET @longtext = 'Lorem ipsum dolor sit amet, consectetur adipiscing elit. Donec vitae odio tellus, sit amet facilisis neque. Cras sapien nulla, suscipit non imperdiet ac, aliquet vitae lectus. Nulla a varius dolor. Nunc convallis, augue et fermentum volutpat, lectus urna sagittis risus, vel iaculis diam est convallis lectus. Suspendisse potenti. Morbi malesuada tristique varius.';

SELECT SUBSTRING(
    @longtext,
    1,
    300 - ifnull(
        LOCATE(
            '.',
            REVERSE(
                SUBSTRING(
                    @longtext,
                    1,
                    300
                )
            )
        ),
    1)
);

Answer 1

Okay, so I think I’ve got it; comments are unfortunately in reverse due to the nature of the thing…

select substr('my_string', 1
            -- 300 - distance from the first '.' in the reversed string.
             , 300 - ifnull(
                           -- Get the 1st position of the '.' in the
                           -- reversed string.
                            locate('.', reverse(substr('my_string',1,300))
                                  )
                          -- if it's null, i.e. doesn't exist, replace it with 1.
                           , 1)
              )

You can change the 300 as you wish.