The few worth knowing.
SUM AND AVERAGE
Totals and means. Obvious and constantly used.
CONDITIONAL SUM AND COUNT
Totalling or counting only records meeting a condition.
The most useful functions there are.
LOOKUP FUNCTIONS
Bringing a value from one table into another using a common identifier.
How you join customer names to sales.
IF
Applying a rule: categorise, flag, or branch.
DATE FUNCTIONS
Extracting month or year from a date, so you can group by period.
TEXT FUNCTIONS
Cleaning: trimming spaces, changing case, splitting values.
UNIQUE AND COUNTING DISTINCT
Finding how many different customers, products or categories exist.
ROUNDING
Presenting figures sensibly.
WHAT TO LEARN IN ORDER
Conditional sum, lookup, date extraction.
Those three enable most business analysis.
WHAT NOT TO DO
Build elaborate formulas you will not understand later.
WHAT TO PREFER
Several simple steps in separate columns over one complicated formula.
