InfluxDB中的多个WHERE不返回结果

我正在使用telegraf将snmp数据推送到我的InfluxDB并通过Grafana进行可视化.

现在我遇到了一个奇怪的问题(很可能只是我身边的一个误解......)

鉴于以下系列:

snmp,agent_host=10.20.30.40,host=grafana-dev,hostname=1OG,ifIndex=3,ifName=ath0
snmp,agent_host=10.20.30.40,host=grafana-dev,hostname=1OG,ifIndex=3,ifName=ath1

我目前在grafana中使用以下查询来获取数据(工作正常):

SELECT 
non_negative_derivative(mean("ifInOctets"), 1s) *8 AS "In", 
non_negative_derivative(mean("ifOutOctets"), 1s) *8 AS "Out" 
FROM "snmp" 
WHERE "host" = 'grafana-dev' 
AND "hostname" =~ /^1OG$/ 
AND time > now() - 6h 
GROUP BY time(10s), "hostname", "ifName" fill(null)&epoch=ms

我现在只需要为单个接口选择数据(ifName):

SELECT 
non_negative_derivative(mean("ifInOctets"), 1s) *8 AS "In", 
non_negative_derivative(mean("ifOutOctets"), 1s) *8 AS "Out" 
FROM "snmp" 
WHERE "host" = 'grafana-dev' 
AND "hostname" =~ /^1OG$/ 
AND "ifName"= 'ath0'
AND time > now() - 6h 
GROUP BY time(10s), "hostname", "ifName" fill(null)&epoch=ms

但这并没有带来任何结果,尽管应该有很多.

我真的很感激任何提示是什么问题......

干杯