Adding upstream version 1.13.0.upstream/1.13.0

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 25 insertions, 0 deletions

diff --git a/iredis/data/commands/zintercard.md b/iredis/data/commands/zintercard.md
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+This command is similar to `ZINTER`, but instead of returning the result set, it returns just the cardinality of the result.
+
+Keys that do not exist are considered to be empty sets.
+With one of the keys being an empty set, the resulting set is also empty (since set intersection with an empty set always results in an empty set).
+
+By default, the command calculates the cardinality of the intersection of all given sets.
+When provided with the optional `LIMIT` argument (which defaults to 0 and means unlimited), if the intersection cardinality reaches limit partway through the computation, the algorithm will exit and yield limit as the cardinality.
+Such implementation ensures a significant speedup for queries where the limit is lower than the actual intersection cardinality.
+
+@return
+
+@integer-reply: the number of elements in the resulting intersection.
+
+@examples
+
+```cli
+ZADD zset1 1 "one"
+ZADD zset1 2 "two"
+ZADD zset2 1 "one"
+ZADD zset2 2 "two"
+ZADD zset2 3 "three"
+ZINTER 2 zset1 zset2
+ZINTERCARD 2 zset1 zset2
+ZINTERCARD 2 zset1 zset2 LIMIT 1
+```