Search for text between delimiters in MySQL

Question

I am trying to extract a certain part of a column that is between delimiters.

e.g. find foo in the following

test \'esf :foo: bar

So in the above I\'d wa

Answer 1

mid(col, 
    locate('?m=',col) + char_length('?m='), 
    locate('&o=',col) - locate('?m=',col) - char_length('?m=') 
)

A bit compact form by replacing char_length(.) with the number 3

mid(col, locate('?m=',col) + 3, locate('&o=',col) - locate('?m=',col) - 3)

the patterns I have used are '?m=' and '&o'.

Answer 2

This one looks elegant to me. Strip all after n-th separator, rotate string, strip everything after 1. separator, rotate back.

select
  reverse(
    substring_index(
      reverse(substring_index(str,separator,substrindex)),
      separator,
      1)
  );

For example:

select
  reverse(
    substring_index(
      reverse(substring_index('www.mysql.com','.',2)),
      '.',
      1
    )
  );

Answer 3

This should work if the two delimiters only appear twice in your column. I am doing something similar...

substring_index(substring_index(column,':',-2),':',1)

Answer 4

you can use the substring / locate function in 1 command

here is a mice tutorial:

http://infofreund.de/mysql-select-substring-2-different-delimiters/

The command as describes their should look for u:

**SELECT substr(text,Locate(' :', text )+2,Locate(': ', text )-(Locate(' :', text )+2)) FROM testtable**

where text is the textfield which contains "test 'esf :foo: bar"

So foo can be fooooo or fo - the length doesnt matter :).

Answer 5

I don't know if you have this kind of authority, but if you have to do queries like this it might be time to renormalize your tables, and have these values in a lookup table.

Answer 6

select mid(col from locate(':',col) + 1 for 
locate(':',col,locate(':',col)+1)-locate(':',col) - 1 ) 
from table where col rlike ':.*:';