Analytically compare the plot in Jazz and Song of Solomon. (Does Jazz really have a traditional plot structure since the narrator is not consistent in telling whole stories at one time?)
As you rightly point out in your question, Jazz does not have a traditional plot structure. The stories of the love triangle between Violet, Joe, and Dorcas are interspersed with stories of characters on the periphery, such as those of Vera Louise Gray and Golden Gray, her son, but none of these narratives are related to the reader in a straight-forward fashion. Along with these sometimes-frustrating digressions, the style of Jazz is frequently stream-of-consciousness. Further complicating matters are the great number of flashbacks that dip far back into the past and shift between Harlem and Virginia. Here is an example of all of those literary devices in this musing from Violet:
“I’m crazy about this City.
Daylight slants like a razor cutting the buildings in half. In the top half I see looking faces and it’s not easy to tell which are people, which the work of stonemasons. Below is shadow where any blasé thing takes place: clarinets and lovemaking, fists and the voices of sorrowful women. A city like this one makes me dream tall and feel in on things. Hep. It’s the bright steel rocking above the shade below that does it. When I look over strips of green grass lining the river, at church steeples and into the cream-and-copper halls of apartment buildings, I’m strong. Alone, yes, but top-notch and indestructible-like the City in 1926 when all the wars are over and there will never be another one. The people down there in the shadow are happy about that. At last, at last, everything’s ahead. The smart ones say so and people listening to them and reading what they write down agree: Here comes the new. Look out.”
As for Song of Solomon, this novel is much more "normal," in the way the narrative is presented, anyway. The genre is called "bildungsroman" ("coming-of-age"). The protagonist of the story is a boy nicknamed "Milkman," and follows him as from his birth, through his youth, and to maturity. Here is an example of Milkman as he makes the painful journey to maturation:
“They hooted and laughed all the way back to the car, teasing Milkman, egging him on to tell more about how scared he was. And he told them. Laughing too, hard, loud, and long. Really laughing, and he found himself exhilarated by simply walking the earth. Walking it like he belonged on it; like his legs were stalks, tree trunks, a part of his body that extended down down down into the rock and soil, and were comfortable there--on the earth and on the place where he walked. And he did not limp.”