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.PKS File Extension

File Type	Oracle Package Spec File
File Format	File
Common?	No
File Description	Package specifications file created by Oracle PL/SQL software; contains specifications, TYPE definitions, and predefined exceptions for an Oracle Package (.PKB) file.
Program(s) that open pks files	Windows: Oracle PL/SQL software; View in a text editor

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http://www.fileinfo.com/extension/pks