You can use Plsql_developer without installing oracle_client

1. Download the Oracle Client package (30M)

Only need to download a software called Instant Client package on the official Oracle website, this software does not need to be installed, as long as the decompression can be used, very convenient, even if the system is re-installed can be used.

：
Http://www.oracle.com/technology/software/tech/oci/instantclient/htdocs/winsoft.html
Unzip to a directory, e.g. C:\oracleclient
2. Configure operating system environment variables
Nls_lang=simplified Chinese_china. Zhs16gbk
Tns_admin=c:\oracleclient\network\admin
3. Configure the configuration to connect to Oracle. Tnsnames.ora file to directory C:\oracleclient. You can copy one from the Oracle server.
4. Install Plsql Developer
5. Configure Plsql Developer (the first time you can go directly to Plsql Developer without logging in)
Tools--Preferences--> Connections,
Oracle Home content is C:\oracleclient
OCI Library content is C:\oracleclient\oci.dll
Restart Plsqldeveloper
Complete

You can use Plsql_developer without installing oracle_client