Reading an Apex debug log without losing the afternoon
A real 4 MB log from a real failed deployment, and the four search strings that find the problem in minutes.
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A debug log is not meant to be read top to bottom — it is meant to be searched. This walkthrough takes an actual four-megabyte log from a failed deployment and finds the failing assertion in about three minutes, using nothing but the log levels panel and four search strings worth memorising:
FATAL_ERROR— the end of the story, so start thereEXCEPTION_THROWN— the beginning of itSOQL_EXECUTE_BEGIN— count them; if the count moves with batch size, there is your loopCUMULATIVE_LIMIT_USAGE— the receipt
The one setting that matters before any of this: APEX_CODE, FINEST on the
class you suspect and ERROR on everything else. A log at FINEST across the
whole org truncates at 20 MB, usually just before the interesting part.
