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create table mytable(id int, mycol varchar(2000));
insert into mytable values (
1,
'{{abcd{{WoodhouseENELnames
|Text=[[File:woodhouse_999.jpg|thumb|link={{filepath:woodhouse_999.jpg}}]]Αἰακός, ὁ, or say, son of Aegina.
<b class="b2">Of Aeacus</b>, adj.: Αἰάκειος.
<b class="b2">Descendant of Aeacus</b>: Αἰακίδης, -ου, ὁ.
}} efgh{{'
)
select * from mytable;
| id | mycol |
|---|---|
| 1 | {{abcd{{WoodhouseENELnames |Text=[[File:woodhouse_999.jpg|thumb|link={{filepath:woodhouse_999.jpg}}]]Αἰακός, ὁ, or say, son of Aegina. <b class="b2">Of Aeacus</b>, adj.: Αἰάκειος. <b class="b2">Descendant of Aeacus</b>: Αἰακίδης, -ου, ὁ. }} efgh{{ |
with recursive cte as (
select
n_open n0,
n_open n1,
1 cnt,
mycol,
id
from (select t.*, locate('{{WoodhouseENELnames', mycol) n_open from mytable t) x
where n_open > 0
union all
select
n0,
n1 + 2 + case when n_open > 0 and n_open < n_close then n_open else n_close end,
cnt + case when n_open > 0 and n_open < n_close then 1 else -1 end,
mycol,
id
from (
select
c.*,
locate('{{', substring(mycol, n1 + 2)) n_open,
locate('}}', substring(mycol, n1 + 2)) n_close
from cte c
) x
where cnt > 0
)
select id, concat(substring(mycol, 1, min(n0) - 1), substring(mycol, max(n1) + 1)) mycol
from cte
group by id
| id | mycol |
|---|---|
| 1 | {{abcd efgh{{ |