 COMMENT ON TABLE "api_client" IS 'Registered OAuth2 client for a member';
 
 COMMENT ON COLUMN "api_client"."member_id"            IS 'Member, who registered the client for him/herself, or NULL for clients registered by administrator';
-COMMENT ON COLUMN "api_client"."name"                 IS 'Name of the client as chosen by member or administrator';
+COMMENT ON COLUMN "api_client"."name"                 IS 'Name of the client as chosen by member or administrator, NULL means unnamed';
 COMMENT ON COLUMN "api_client"."client_identifier"    IS 'OAuth2 client id, also used as redirection endpoint if "member_authorization" is set to TRUE';
 COMMENT ON COLUMN "api_client"."client_secret"        IS 'Secret for client authentication, enables OAuth2 Client Credentials Grant when set';
 COMMENT ON COLUMN "api_client"."member_authorization" IS 'Allow OAuth2 Authorization Code Grant and Implicit Grant, in which case the "client_identifier" is used as the redirection endpoint';
 COMMENT ON COLUMN "api_client"."public_access_level"  IS 'Access level for OAuth2 Client Credentials Grant';
 COMMENT ON COLUMN "api_client"."access_level"         IS 'Access level for OAuth2 Authorization Code Grant and Implicit Grant';
-COMMENT ON COLUMN "api_client"."parallel_access"      IS 'Multiple entries in "api_access" table allowed';
 COMMENT ON COLUMN "api_client"."validity_period"      IS 'Period after which an entry in the "api_access" table expires';
 
 

                                                ON DELETE CASCADE ON UPDATE CASCADE,
        "member_id"             INT4            REFERENCES "member" ("id")
                                                ON DELETE CASCADE ON UPDATE CASCADE,
        "created"               TIMESTAMPTZ     NOT NULL DEFAULT now(),
        "authorization_code"    TEXT,
        "refreshed"             TIMESTAMPTZ,

        "member_authorization"  BOOLEAN         NOT NULL,
        "public_access_level"   "api_access_level",
        "access_level"          "api_access_level" NOT NULL,
        "validity_period"       INTERVAL        NOT NULL,
        "last_usage"            TIMESTAMPTZ     NOT NULL,
        CONSTRAINT "system_clients_require_name"
          CHECK ("name" NOTNULL OR "member_id" ISNULL),
        CONSTRAINT "public_access_level_set_if_and_only_if_system_client"
          CHECK ("member_id" ISNULL = "public_access_level" NOTNULL) );
CREATE UNIQUE INDEX "api_client_non_member_client_identifier_idx"
