How to fix ( SQLSTATE[HY000] [2002] No connection could be made.. )

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[nazelibrahim]

wow, it's been very simple like this, thanks so much

[PurvajaVashistha]

If I am using Wamp Server, What can I do?

[mazenal-amrawi]

You can help me, sir in this problem
SQLSTATE[HY000] [2002] php_network_getaddresses: getaddrinfo for mysql failed: No such host is known. (SQL: select * from `courses`)