Publish sqlx article.
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@ -9,7 +9,7 @@ for interacting with a SQL database.
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One of the more popular features of `sqlx` is that it does compile time checking
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of database queries (giving you some ORM-ish properties) while still allowing
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you to write straight SQL queries without the abstraction of an ORM though use
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of their [`query!`](https://docs.rs/sqlx/0.5.5/sqlx/macro.query.html).
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of their [`query!`](https://docs.rs/sqlx/0.5.5/sqlx/macro.query.html) macro.
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To make this work, `sqlx` requires:
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@ -19,11 +19,11 @@ To make this work, `sqlx` requires:
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I don't particularly like either of those options, though I admittedly
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have not tried either of them long term.
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Requring a running database at compile time would seem to make compilation
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Requiring a running database at compile time would seem to make compilation
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a lot slower.
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It also adds a unexpected step (run a container hosting a development database)
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It also adds an unexpected step (run a container hosting a development database)
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before you can compile, which just feels wrong.
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The configuation files are better in the sense they don't require a running
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The configuration files are better in the sense they don't require a running
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database at compile time, but it's an extra thing that has to be kept in sync
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with the code.
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@ -35,8 +35,8 @@ to improve in this post.
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The other thing I'll show in this post is working with JSON in Postgres.
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Postgres has native support for working with JSON documents, providing
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a lot of the benefits of NoSQL databases, but in a SQL database.
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`sqlx`'s API for json documents integrates well with serde, and is resonably
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a lot of the benefits of NoSQL databases in a SQL database.
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`sqlx`'s API for json documents integrates well with serde, and is reasonably
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easy to work with.
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# Pre-reqs
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@ -73,8 +73,8 @@ The script:
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# Example
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For the rest of this post, I will walk through our example (which can be found
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[here](https://git.jpace121.net/public/sql-fun/src/branch/main/src/main.rs).
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For the rest of this post, I will walk through an example (which can be found
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[here](https://git.jpace121.net/public/sql-fun/src/branch/main/src/main.rs)).
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``` rust
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use serde::{Deserialize, Serialize};
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@ -110,7 +110,7 @@ The first thing we do in main is to connect to the database by making a connecti
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The `connect` function takes a string argument to control what database by what method
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we want to connect to.
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Specifically, in the call above, we're going to connect as the user `postgres` using the
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password `devpassword` to the server running on `localhost` with the default port, to the
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password `devpassword` to the server running on `localhost` with the default port to the
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database `postgres`.
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```rust
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@ -133,7 +133,7 @@ in it.
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`query` returns a `Query` object which has member functions we call
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to actually do the database call.
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The two functions we'll use in this example are `execute` and `fetch_one`.
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Both functions take the `pool` as an input an return a future with a result
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Both functions take the `pool` as an input and return a future with a result
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that we need to await.
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What's in the non-Err part of the results depends on which function we call.
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For `execute` it is `()`, and thus we call `execute` when we're not expecting to
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@ -157,7 +157,7 @@ query the output of our database query.
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let _ = sqlx::query(&james_add_query).execute(&pool).await?;
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```
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The next thing we do is add rows to table so we have something to query.
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We start by instantiating and instance of our `Doc` struct, and then using
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We start by instantiating an instance of our `Doc` struct, and then using
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`serde_json` to serialize it into a JSON string.
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We generate and execute the database query as before, with the exception that
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we make the string we're going to pass into `sqlx::query` in its own line.
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@ -165,7 +165,7 @@ One thing of interest is we define the string using a "raw string literal"
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(the `r#` stuff).
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The official documentation for the "raw string literal"s is
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[here](https://doc.rust-lang.org/reference/tokens.html#raw-string-literals).
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It's basically a special ysntax that allows us to avoid having to escape characters
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It's basically a special syntax that allows us to avoid having to escape characters
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inside of the string.
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The next block of text is basically the same as above, but for our second user,
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@ -200,12 +200,12 @@ There are three interesting new things in this block of code:
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1. In the SQL query, we're going to use the special syntax `->>` to refer
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to elements inside the JSON object we added to the database.
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2. Since we're trying to get one element from the database, instead of
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call `execute` on the query, we use `fetch_one`.
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calling `execute` on the query, we use `fetch_one`.
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3. The result of `fetch_one` is a `sqlx::Row`.
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To get actual data out of the row we call `try_get`, which takes one
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parameter, the index of the element of the row to get an elemet of.
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parameter, the index of the element of the row to get an element of.
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There are two type parameters for `try_get`, the first the type of the
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thing we're getting from the row and the second the type of index.
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thing we're getting from the row and the second the type of the index.
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```rust
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// Get name based on movie.
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@ -216,7 +216,7 @@ There are three interesting new things in this block of code:
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```
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Our second example is similar to the first, but we use the `->>` syntax to pull
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something out the json doc in the `WHERE` condition instead of in what we `SELECT`.
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something out of the JSON doc in the `WHERE` condition instead of in what we `SELECT`.
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```rust
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