The pg_compression system catalog table describes the compression methods available.

    column type modifers storage description
    compname name not null plain Name of the compression
    compconstructor regproc not null plain Name of compression constructor
    compdestructor regproc not null plain Name of compression destructor
    compcompressor regproc not null plain Name of the compressor
    compdecompressor regproc not null plain Name of the decompressor
    compvalidator regproc not null plain Name of the compression validator
    compowner oid not null plain oid from pg_authid

    Parent topic: System Catalogs Definitions