showAlter table (n, Update' s) =
    concat
    [ "UPDATE "
    , escapeDBName table
    , " SET "
    , escapeDBName n
    , "="
    , s
    , " WHERE "
    , escapeDBName n
    , " IS NULL"
    ]
showAlter table (n, Update' s) =
    concat
    [ "UPDATE "
    , escapeDBName table
    , " SET "
    , escapeDBName n
    , "="
    , s
    , " WHERE "
    , escapeDBName n
    , " IS NULL"
    ]
showAlter table (n, Update' s) =
    concat
    [ "UPDATE "
    , escapeDBName table
    , " SET "
    , escapeDBName n
    , "="
    , s
    , " WHERE "
    , escapeDBName n
    , " IS NULL"
    ]