mysql group_concat not bringing entire data
I am using the following query and utilizing the group_concat
function. However, at times the data in the answers
column is being cut off; meaning I don't get the entire data, in the end it is just chopped off.
I suspect it might have something to do with the datatype....can it be casted to a bigger datatype? Currentl开发者_如何学Pythony the Other1
datatype is text
select SiteName,
case
when group_concat(Other1) is not null
then group_concat( cast(Other1 AS BLOB))
when group_concat(Other1) is null
then 'No Response provided'
end
'answers'
from disparities_community_partnerships
where QuarterId=2
group by SiteName
http://dev.mysql.com/doc/refman/5.0/en/group-by-functions.html#function_group-concat
The result is truncated to the maximum length that is given by the group_concat_max_len system variable, which has a default value of 1024. The value can be set higher, although the effective maximum length of the return value is constrained by the value of max_allowed_packet. The syntax to change the value of group_concat_max_len at runtime is as follows, where val is an unsigned integer
SET [GLOBAL | SESSION] group_concat_max_len = val;
One more sample Example Execute like this
SET GLOBAL group_concat_max_len = 5555555;
select SiteName,
case
when group_concat(Other1) is not null
then group_concat( cast(Other1 AS BLOB))
when group_concat(Other1) is null
then 'No Response provided'
end
'answers'
from disparities_community_partnerships
where QuarterId=2
group by SiteName
Set the group_concat_max_len
before your query:
SET GLOBAL group_concat_max_len = 9999999;
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