Oracle Instant Client-SQL * Plus-错误：没有TNS侦听器（MacOSX）

Question

I am developing a web application that has to be connected with the ORACLE database.

Presently I am working on macOS X and I have downloaded Oracle Instant Client . I am able to run sqlplus , but while logging in the interface I get the following error:

SQL*Plus: Release 12.2.0.1.0 Production on Sun Jul 8 10:55:48 2018

Copyright (c) 1982, 2017, Oracle.  All rights reserved.
Enter user-name: hr
Enter password: 
ERROR:
ORA-12541: TNS:no listener

For your information, I have downloaded nothing except the client software by Oracle and installed it according to the official installation documentation. I really need to work on sqlplus for the database.

PLEASE HELP.

Also, could you please tell me how can I use sqlplus in my machine?

Answer 1

Instant client does not provide you with a Oracle database to work with, they are just tools to connect to a database.From the documentation of Instant Client

Oracle Instant Client enables applications to connect to a local or remote Oracle Database for development and production deployment. The Instant Client libraries provide the necessary network connectivity, as well as basic and high end data features, to make full use of Oracle Database.

So, prior to using an instant client, you need to have an Oracle database somewhere(local or remote).If you have a database server on a remote host, you may connect it using the easy connect syntax.

sqlplus user/pwd@//remote_hostname:1521/remote_dbname

If you have a tnsnames.ora file in your $TNS_ADMIN preconfigured to contain the list of database instances available, you may simply use this to connect

 sqlplus user/pwd@tns_entry_for_DB

Putting the tns entry in command line also works.

 sqlplus user/pwd@(DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(Host=remote_hostname)(Port=1521))(CONNECT_DATA=(SID=remote_dbname)))

Moreover,Oracle doesn't provide you database software versions beyond 10gr2 to install locally on a Mac.

If you want to install and connect to a local database version 12.2 in Mac, One option is to host a virtual machine for Linux/Windows or run a docker container . Please read my post here for details: Oracle SQL for Mac OS X