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# 5 Encoding of returned values

Zabbix server expects every returned text value in the UTF8 encoding.
This is related to any type of checks: Zabbix agent, SSH, Telnet, etc.

Different monitored systems/devices and checks can return non-ASCII
characters in the value. For such cases, almost all possible **zabbix** keys
contain an additional item key parameter - **<encoding>**. This
key parameter is optional but it should be specified if the returned
value is not in the UTF8 encoding and it contains non-ASCII characters.
Otherwise the result can be unexpected and unpredictable.

A description of behavior with different database backends in such cases
follows.

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#### MySQL

If a value contains a non-ASCII character in non UTF8 encoding - this
character and the following will be discarded when the database stores
this value. No warning messages will be written to the
*zabbix\_server.log*.<br>
Relevant for at least MySQL version 5.1.61.

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#### PostgreSQL

If a value contains a non-ASCII character in non UTF8 encoding - this
will lead to a failed SQL query (PGRES\_FATAL\_ERROR:ERROR invalid byte
sequence for encoding) and data will not be stored. An appropriate
warning message will be written to the *zabbix\_server.log*.<br>
Relevant for at least PostgreSQL version 9.1.3.

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