CodeQL documentation

query compile


codeql query compile [--check-only] [--threads=<num>] [--ram=<MB>] <options>... [--] <file>...


Compile or check QL code.

Compile one or more queries. Usually the main outcome of this command is that the compiled version of the query is written to a compilation cache where it will be found when the query is later executed. Other output options are mostly for debugging.



[Mandatory] Queries to compile. Each argument is one of:

  • A .ql file to compile.
  • A directory which will be searched recursively for .ql files.
  • A .qls file that defines a particular set of queries.
  • The basename of a “well-known” .qls file exported by one of the installed QL packs.
-n, --check-only

Just check that the QL is valid and print any errors; do not actually optimize and store a query plan. This can be much faster than a full compilation.


[Advanced] Print the optimized DIL intermediate representation to standard output while compiling.

When JSON output is selected, the DIL will be represented as an array of single-line strings, with some wrapping to identify which query is being compiled.


[Advanced] Print the optimized RA query plan to standard output while compiling.

When JSON output is selected, the RA will be represented as an array of single-line strings, with some wrapping to identify which query is being compiled.


Select output format, either text (the default) or json.

-j, --threads=<num>

Use this many threads to compile queries.

Defaults to 1. You can pass 0 to use one thread per core on the machine, or -N to leave N cores unused (except still use at least one thread).

-M, --ram=<MB>

Set total amount of RAM the compiler should be allowed to use.

QL variant and compiler control options


How to handle warnings from the QL compiler. One of:

hide: Suppress warnings.

show (default): Print warnings but continue with compilation.

error: Treat warnings as errors.


[Advanced] Omit particularly slow optimization steps.


Only perform initial checks on the part of the QL source that is used.


Don’t check embedded query metadata in QLDoc comments for validity.


[Advanced] Override the default maximum size for a compilation cache directory.

Options to set up compilation environment


A list of directories under which QL packs may be found. Each directory can either be a QL pack (or bundle of packs containing a .codeqlmanifest.json file at the root) or the immediate parent of one or more such directories.

If the path contains more than directory, their order defines precedence between them: when a pack name that must be resolved is matched in more than one of the directory trees, the one given first wins.

Pointing this at a checkout of the open-source CodeQL repository ought to work when querying one of the languages that live there.

If you have have checked out the CodeQL reposity as a sibling of the unpacked CodeQL toolchain, you don’t need to give this option; such sibling directories will always be searched for QL packs that cannot be found otherwise. (If this default does not work, it is strongly recommended to set up --search-path once and for all in a per-user configuration file).

(Note: On Windows the path separator is ;).


If this list of directories is given, they will be searched for packs before the ones in --search-path. The order between these doesn’t matter; it is an error if a pack name is found in two different places through this list.

This is useful if you’re temporarily developing a new version of a pack that also appears in the default path. On the other hand, it is not recommended to override this option in a config file; some internal actions will add this option on the fly, overriding any configured value.

(Note: On Windows the path separator is ;).


[Advanced] An optional list of directories that will be added to the raw import search path for QL libraries. This should only be used if you’re using QL libraries that have not been packaged as QL packs.

(Note: On Windows the path separator is ;).


[Advanced] Explicitly define which dbscheme queries should be compiled against. This should only be given by callers that are extremely sure what they’re doing.


[Advanced] Specify an additional directory to use as a compilation cache.


[Advanced] Don’t use compilation caches in standard locations such as in the QL pack containing the query or in the CodeQL toolchain directory.

Common options

-h, --help

Show this help text.


[Advanced] Give option to the JVM running the command.

(Beware that options containing spaces will not be handled correctly.)

-v, --verbose

Incrementally increase the number of progress messages printed.

-q, --quiet

Incrementally decrease the number of progress messages printed.


[Advanced] Explicitly set the verbosity level to one of errors, warnings, progress, progress+, progress++, progress+++. Overrides -v and -q.


[Advanced] Write detailed logs to one or more files in the given directory, with generated names that include timestamps and the name of the running subcommand.

(To write a log file with a name you have full control over, instead give --log-to-stderr and redirect stderr as desired.)