From 06cba6ccd165ca8b224797e37fccb9e63f026d77 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 21 Mar 2020 11:28:17 +0100 Subject: Adding upstream version 1.9.1. Signed-off-by: Daniel Baumann --- iredis/data/commands/getset.md | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) create mode 100644 iredis/data/commands/getset.md (limited to 'iredis/data/commands/getset.md') diff --git a/iredis/data/commands/getset.md b/iredis/data/commands/getset.md new file mode 100644 index 0000000..20b86a2 --- /dev/null +++ b/iredis/data/commands/getset.md @@ -0,0 +1,28 @@ +Atomically sets `key` to `value` and returns the old value stored at `key`. +Returns an error when `key` exists but does not hold a string value. + +## Design pattern + +`GETSET` can be used together with `INCR` for counting with atomic reset. For +example: a process may call `INCR` against the key `mycounter` every time some +event occurs, but from time to time we need to get the value of the counter and +reset it to zero atomically. This can be done using `GETSET mycounter "0"`: + +```cli +INCR mycounter +GETSET mycounter "0" +GET mycounter +``` + +@return + +@bulk-string-reply: the old value stored at `key`, or `nil` when `key` did not +exist. + +@examples + +```cli +SET mykey "Hello" +GETSET mykey "World" +GET mykey +``` -- cgit v1.2.3