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Queries, which has a language attribute set to the identifier

ql file itself is the queryĪ queries.xml file that defines a query directory must always If there is no suchĭirectory, the directory of the. Where such a file is found is the query directory. Walking up the directory structure, each directory is checked for aįile called queries.xml or qlpack.yml. Starting with the directory containing the. This section describes the defaultįirst, determine the query directory of the. Particular invocation, though that is rarely done, and only Tools also allow you to explicitly specify the library path on the command line for a Implementations of QL construct it in slightly different ways. Speaking a core part of the QL language, since different It is usedįor resolving module imports (see “ Module resolution”). The library path is an ordered list of directory locations. An implementation of QL must detect all invalid programs and refuse to evaluate them.

The library path is a sequence of file-system directories that hold QLL files.Ī QL program can be evaluated (see “ Evaluation”) to produce a set of tuples of values (see “ Values”).įor a QL program to be valid, it must conform to a variety of conditions that are described throughout this specification otherwise the program is said to be invalid. The database provides a number of definitions: database types (see “ Types”), entities (see “ Values”), built-in predicates (see “ Built-ins”), and the database content of built-in predicates and external predicates (see “ Evaluation”).

QL programs are interpreted in the context of a database and a library path. A module may also include import directives (see “ Import directives”), non-member predicates (see “ Non-member predicates”), class definitions (see “ Classes”), and module definitions (see “ Modules”). The module in the QL file includes one or more queries (see “ Queries”). A QL program consists of a query module defined in a QL file and a number of library modules defined in QLL files that it imports (see “ Import directives”).