string is too long to be intercepted when synchronizing data into ES by plugin jdbc with using mysql "group_concat" function

[mingjia-vip]

string is too long to be intercepted when synchronizing data into ES by plugin jdbc with using mysql "group_concat" function :

Version: ES 2.3
Operating System: centos7
Steps to Reproduce:
1，sql:select id,group_concat(str) as long_str from long_str_test
2，long_str‘s length longer than 350 characters
3，import into ES by plugin jdbc，the value of long_str be intercepted, length is 343.

[jprante]

What is value of group_concat_max_len?

https://dev.mysql.com/doc/refman/5.7/en/server-system-variables.html#sysvar_group_concat_max_len