1. A computer-implemented method comprising: accessing in memory a set of events, each event identified by an associated time stamp; wherein each event in the set of events includes a portion of raw data; receiving data indicating selection of a first event from among a first plurality of events and data indicating a selection of one or more portions of text within the raw data of the first event to be extracted as one or more fields; automatically determining an initial extraction rule that extracts the selected portions of text within the first event; causing display of a first interface providing tools that implement user modification of the extraction rule, including selecting a field from the one or more fields and: selecting one or more non-adjoining strings to concatenate with the selected field; selecting a portion of the selected field to be trimmed from the beginning or end of the selected field; or selecting sub-portions of text to extract from within the selected field.
1. A computer-implemented method comprising: accessing in memory a set of events, each event identified by an associated time stamp; wherein each event in the set of events includes a portion of raw data; receiving data indicating selection of a first event from among a first plurality of events and data indicating a selection of one or more portions of text within the raw data of the first event to be extracted as one or more fields; automatically determining an initial extraction rule that extracts the selected portions of text within the first event; causing display of a first interface providing tools that implement user modification of the extraction rule, including selecting a field from the one or more fields and: selecting one or more non-adjoining strings to concatenate with the selected field; selecting a portion of the selected field to be trimmed from the beginning or end of the selected field; or selecting sub-portions of text to extract from within the selected field. 7. The method of claim 1 , further including: receiving further data indicating a selection to validate the extraction rule; causing display of a second user interface including an annotated version of the plurality of events, wherein the annotated version indicates the portions of text within the plurality of events extracted by the field extraction rule and provides one or more user controls that implement user selection of indicated portions of the text as examples of text that should not be extracted; receiving further data indicating a selection of one or more examples of text that should not be extracted; and automatically determining an updated field extraction rule that does not extract the text that should not be extracted.