Increment operation error: Failed to increment value in the server: Not a number

Couchbase Server 2.5.0
PHP SDK version 1.2

Could you share some code snippet, also what flags/value that key does have?

I general that error means that the value itself cannot be represented as a number. Consider the example (sorry it is in ruby, but it also uses libcouchbase).

require 'couchbase'

conn = Couchbase.connect
conn.set(“foo”, “bar”)

~> Couchbase::Error::DeltaBadval: failed to perform arithmetic operation (key=“foo”, error=0x03)

~> [No Name]:5:in `incr’

~> [No Name]:5:in `’