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Update README.md

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Eitan Chatav 2019-10-28 09:41:06 -07:00
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@ -180,8 +180,8 @@ DROP TABLE "emails";
DROP TABLE "users";
```
We'll need a Haskell type for @User@s. We give the type `Generics.SOP.Generic` and
`Generics.SOP.HasDatatypeInfo` instances so that we can encode and decode @User@s.
We'll need a Haskell type for `User`s. We give the type `SOP.Generic` and
`SOP.HasDatatypeInfo` instances so that we can encode and decode `User`s.
```Haskell
>>> data User = User { userName :: Text, userEmail :: Maybe Text } deriving (Show, GHC.Generic)
@ -189,12 +189,12 @@ We'll need a Haskell type for @User@s. We give the type `Generics.SOP.Generic` a
>>> instance SOP.HasDatatypeInfo User
```
Next, we'll write `Manipulation_`s to insert @User@s into our two tables.
Next, we'll write `Manipulation_`s to insert `User`s into our two tables.
A `Manipulation_` like `insertInto`, `update` or `deleteFrom`
has three type parameters, the schemas it refers to, input parameters
and an output row. When
we insert into the users table, we will need a parameter for the @name@
field but not for the @id@ field. Since it's serial, we can use a default
we insert into the users table, we will need a parameter for the `name`
field but not for the `id` field. Since it's serial, we can use a default
value. However, since the emails table refers to the users table, we will
need to retrieve the user id that the insert generates and insert it into
the emails table. We can do this in a single `Manipulation_` by using a