flush-commands-docs (#872)

* flush-commands-docs

* Update index.md

* Apply review comments.

* Update index.md

* Apply review comments.

* Apply review comments.

Co-authored-by: andy-stark-redis <164213578+andy-stark-redis@users.noreply.github.com>

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Co-authored-by: David Dougherty <david.dougherty@redis.com>
Co-authored-by: andy-stark-redis <164213578+andy-stark-redis@users.noreply.github.com>

Author: 3 people

content/commands/flushall/index.md

@@ -66,6 +66,7 @@ It is possible to use one of the following modifiers to dictate the flushing mod
 
 * An asynchronous `FLUSHALL` command only deletes keys that were present at the time the command was invoked. Keys created during an asynchronous flush will be unaffected.
 * This command does not delete functions.
+* Other than emptying all databases (similar to `FLUSHDB`), this command clears the RDB persistence file, aborts any snapshot that is in progress, and, if the `save` config is enabled, saves an empty RDB file.
 
 ## Behavior change history
 

content/commands/flushdb/index.md

@@ -66,6 +66,7 @@ It is possible to use one of the following modifiers to dictate the flushing mod
 
 * An asynchronous `FLUSHDB` command only deletes keys that were present at the time the command was invoked. Keys created during an asynchronous flush will be unaffected.
 * This command does not delete functions.
+* When using Redis Cluster, this command is identical to `FLUSHALL` since a Redis Cluster supports only one database with an ID of zero.
 
 ## Behavior change history