это не из-за даунгрейда. это какой-то кривой sql
не похоже:
INSERT INTO nginx.webservers (logdate, logdatetime, hostname, syslogtag, message, clientip, ident, auth, verb, request, httpv, response, bytes, referrer, agent, blob ) values ('2020-08-03', '2020-08-03 15:19:09', 'pubweb1', 'nginx', 'XXX - - [03/Aug/2020:15:19:09 +0000] \"GET /packages/mainline/debian/dists/stretch/InRelease HTTP/1.1\" 200 2866 \"-\" \"Debian APT-HTTP/1.3 (1.4.10)\" \"-\"', 'XXX', '-', '-', 'GET', '/packages/mainline/debian/dists/stretch/InRelease', '1.1', '200', '2866', '-', 'Debian APT-HTTP/1.3 (1.4.10)', '');
logdate Date
logdatetime DateTime
hostname String
syslogtag String
message String
clientip String
ident String
auth String
verb String
request String
httpv String
response UInt16
bytes UInt64
referrer String
agent String
blob String