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Diffstat (limited to 'iredis/data/commands/pfadd.md')
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diff --git a/iredis/data/commands/pfadd.md b/iredis/data/commands/pfadd.md new file mode 100644 index 0000000..e8e3f03 --- /dev/null +++ b/iredis/data/commands/pfadd.md @@ -0,0 +1,33 @@ +Adds all the element arguments to the HyperLogLog data structure stored at the +variable name specified as first argument. + +As a side effect of this command the HyperLogLog internals may be updated to +reflect a different estimation of the number of unique items added so far (the +cardinality of the set). + +If the approximated cardinality estimated by the HyperLogLog changed after +executing the command, `PFADD` returns 1, otherwise 0 is returned. The command +automatically creates an empty HyperLogLog structure (that is, a Redis String of +a specified length and with a given encoding) if the specified key does not +exist. + +To call the command without elements but just the variable name is valid, this +will result into no operation performed if the variable already exists, or just +the creation of the data structure if the key does not exist (in the latter case +1 is returned). + +For an introduction to HyperLogLog data structure check the `PFCOUNT` command +page. + +@return + +@integer-reply, specifically: + +- 1 if at least 1 HyperLogLog internal register was altered. 0 otherwise. + +@examples + +```cli +PFADD hll a b c d e f g +PFCOUNT hll +``` |