0e036d0 · squeal · git.iko.soy

180DROP TABLE "users";

181```

182

183−We'll need a Haskell type for @User@s. We give the type `Generics.SOP.Generic` and

183+We'll need a Haskell type for `User`s. We give the type `SOP.Generic` and

184−`Generics.SOP.HasDatatypeInfo` instances so that we can encode and decode @User@s.

184+`SOP.HasDatatypeInfo` instances so that we can encode and decode `User`s.

185

186```Haskell

187>>> data User = User { userName :: Text, userEmail :: Maybe Text } deriving (Show, GHC.Generic)

189>>> instance SOP.HasDatatypeInfo User

190```

191

192−Next, we'll write `Manipulation_`s to insert @User@s into our two tables.

192+Next, we'll write `Manipulation_`s to insert `User`s into our two tables.

193A `Manipulation_` like `insertInto`, `update` or `deleteFrom`

194has three type parameters, the schemas it refers to, input parameters

195and an output row. When

196−we insert into the users table, we will need a parameter for the @name@

196+we insert into the users table, we will need a parameter for the `name`

197−field but not for the @id@ field. Since it's serial, we can use a default

197+field but not for the `id` field. Since it's serial, we can use a default

198value. However, since the emails table refers to the users table, we will

199need to retrieve the user id that the insert generates and insert it into

200the emails table. We can do this in a single `Manipulation_` by using a