Setting a line in chart to represent as warning

[bhavna_jain]

Hi,
I want to draw two lines as warning boundaries in a line chart. The string goes "index="ong_poc_index" sourcetype="csv-3-2" Date="20-Apr-12" | where Reading_b1>0 | chart avg(Reading_b1) by Time". I have to draw two lines parallel to X-Axis at 50 and the other at 65 (50 & 65 are readings on Y-Axis). Please help me with some solution.
Thanks in adv.

[martin_mueller]

You could add two more columns to your result table like this:

... | eval lower_warning = 50 | eval upper_warning = 65

[bhavna_jain]

It worked, thank you very much.