There is friendly vulgarity and there is ugly vulgarity.In crossing the street from CBS to ABC, supreme banana Harvey Korman has also moved from the benigh daffiness of the Carol Burnett and Danny Kaye shows on which he excelled into the unsavory realm of sniggering sexcapades for the Clearasil set.

It's almost as if Olivier had agreed to appear in "The Texas Chainsaw Massacre" or signed on for the role of the Tidy Bowl man.

"The Harvey Korman Show," which begins a test run (for possible fall scheduling) at 9:30 tonight on Channel 7, is such a poor attempt to exploit Korman's broad gifts for farce and comic characterization that it seems an act of willful sabotage.

It becomes obvious pretty quickly that the creators of the series decided among themselves that Korman had to be updated and made hip - hip in that square, dull, agonizingly predictable ABC sit-com way. And so the Korman debut, in the old "Soap" time slot and just after the cutey-pie smut of "Three's Company," finds him the captive of a script in which the blue lines turn purple even as they are being spoken by the actors.

Korman is playing a likeable ham whose tattered theatrical career gets repeatedly interrupted by his problem daughter Maggie. The opening plot hinges on a stale modern chestnut; the daughter wants her boyfriend to become a live-in companion, an so naturally Korman as the aghast daddy spends 20 minutes hounding the intruder from the house.

The Oedpial overtones of this banal situation are grievous enough between the lines of Carol Gary's script, but when she elects to make them explicit, the program degenerates into a smarmy languor that makes one long for the '50s and those innocuous sit-com plots about the husband's boss coming over for dinner and the wife burning the roast.

Speaking of her father to her boyfriend, Maggie smirks, "I give you things that he doesn't get," and you can hear the studio audience audibly rolling its eyes and licking its chops, as if witnessing audacity personified. This is not the sort of thing that Norman Lear meant to make television safe for, however.

Built into the script are opportunities for Korman to do some of the flamboyant clowning that made him so indispensable to Burnett; physically, he is an impeccable comedian. The mere act of backing into a prop pitchfork is carried off with the assurance of someone instinctively comedic.

But Korman thrives in the company of other comic talents, and on this show, in addition to being conceptually abandoned, he has no support from other actors. Christine Lahti is pleasingly tart as the daughter but exists mainly as the shadow of a personality. Barry Van Dyke, who plays boyfriend Stuart, is merely a physique.

One can see the computer-dictated elements at work in this project and they creak as the half-hour plays out. You have to wonder even about a computer, however, that thinks people want to see Korman in this kind of non-role doing this kind of comedy, when the kind he does best is so painfully sparse on television.

If he must be locked into a sit-com format, Korman should at least be allowed to play a broder, less domesticated character - one can imagine him as a sort of Uncle Mame, refusing to capitulate to strictures of custom and social behavior. Korman is a giant in the literal and probably professional sense as well, and it's a pity to see someone larger than life being squeezed into a vehicle considerably smaller than a bread box, and not much funnier.