MySQL truncate text with ellipsis

问题

Suppose I have a MySQL table of one column: "Message". It is of type TEXT. I now want to query all rows, but the text can be large (not extremely large but large) and I only want to get a summary of them. For example the result can be populated into a list.

Is there a way to trim the text to a specific length (say, 10 characters), and add ellipsis if the text is trimmed?

For example:

Message
-----------
12345678901234
1234567890
12345
12345678901

Query result:

1234567...
1234567890
12345
1234567...

Thanks!

回答1:

select case when length(message) > 7 
then concat(substring(message, 1, 7), '...')
else message end as adapted_message
from ...

to test/confirm:

SELECT CASE WHEN LENGTH('1234567890') > 7 
THEN CONCAT(SUBSTRING('1234567890', 1, 7), '...') 
ELSE '1234567890' END AS adapted_message

UNION  

SELECT CASE WHEN LENGTH('12345') > 7 
THEN CONCAT(SUBSTRING('12345', 1, 7), '...') 
ELSE '12345' END AS adapted_message

回答2:

or...

SELECT CONCAT(LEFT(message, 7), IF(LENGTH(message)>7, "…", ""))
FROM table

回答3:

Here's a simple one line solution:

IF(CHAR_LENGTH(message) > 10, CONCAT(LEFT(message, 7),"..."), message)

回答4:

Have a look at the MySQL string functions, documented here. You should be able to use some combination of substring and concat to achieve your desired behaviour.

来源：https://stackoverflow.com/questions/6384102/mysql-truncate-text-with-ellipsis