add a sql server example

Author: lovasoa

Cargo.lock

@@ -18,7 +18,7 @@ panic = "abort"
 codegen-units = 2
 
 [dependencies]
-sqlx = { package = "sqlx-oldapi", version = "0.6.35", features = [
+sqlx = { package = "sqlx-oldapi", version = "0.6.36", features = [
     "any",
     "runtime-actix-rustls",
     "sqlite",

Cargo.toml

@@ -0,0 +1,34 @@
+# Handling json data in Microsoft SQL Server
+
+This demonstrates both how to produce and read json data from a SQL query
+in MS SQL Server (or Azure SQL Database), for creating advanced forms.
+
+This lets your user interact with your database with a simple web interface,
+even when you have multiple tables, with one-to-many relationships.
+
+![](./screenshots/app.png)
+
+## Documentation
+
+SQLPage requires JSON to create multi-select input (dropdowns where an user can select multiple values).
+The result of these multi-selects is a JSON array, which also needs to be read by SQL queries.
+
+This example demonstrates how to consume [JSON](https://en.wikipedia.org/wiki/JSON) data from a SQL Server database,
+using the [`OPENJSON`](https://docs.microsoft.com/en-us/sql/t-sql/functions/openjson-transact-sql)
+function to parse the JSON data into a table,
+and [`FOR JSON PATH`](https://docs.microsoft.com/en-us/sql/t-sql/functions/for-json-sql-server)
+to format query results as a JSON array.
+
+
+This demonstrates an application designed for managing groups and users, allowing the creation of new groups, adding users, and assigning users to one or multiple groups. 
+
+The application has the following sections:
+
+- **Create a New Group**: A form where users can enter the name of a new group.
+- **Groups Display**: A list of existing groups.
+- **Add a User**: A form where users can enter the name of a new user and select one or multiple groups to assign to this user.
+- **Users Display**: A list of existing users and their associated group memberships.
+
+When users submit the form, their selections are packaged up and sent to the database server. The server receives these selections as a structured JSON array.
+
+The database then takes this list of selections and temporarily converts it into a format it can work with using the `OPENJSON` function, before saving the information permanently in the database tables. This allows the system to process multiple selections at once in an efficient way.

examples/microsoft sql server advanced forms/README.md

@@ -0,0 +1,32 @@
+services:
+  web:
+    image: lovasoa/sqlpage:main
+    ports:
+      - "8080:8080"
+    volumes:
+      - .:/var/www
+      - ./sqlpage:/etc/sqlpage
+    depends_on:
+      - db
+    environment:
+      RUST_LOG: sqlpage=debug
+      DATABASE_URL: mssql://sa:YourStrong!Passw0rd@db:1433/
+  db:
+    ports:
+      - "1433:1433"
+    image: mcr.microsoft.com/mssql/server:2022-latest
+    volumes:
+      - ./sqlpage/mssql-migrations:/migrations
+    environment:
+      ACCEPT_EULA: Y
+      MSSQL_SA_PASSWORD: YourStrong!Passw0rd
+      MSSQL_PID: Express
+    command: >
+      bash -c "
+        /opt/mssql/bin/sqlservr &
+        until /opt/mssql-tools18/bin/sqlcmd -S localhost -U sa -P YourStrong!Passw0rd -C -Q 'SELECT 1;'; do
+          echo 'Waiting for database...'
+          sleep 1
+        done
+        /opt/mssql-tools18/bin/sqlcmd -S localhost -U sa -P YourStrong!Passw0rd -C -i /migrations/0001_db_init.sql
+        tail -f /dev/null"

examples/microsoft sql server advanced forms/docker-compose.yml

@@ -0,0 +1,37 @@
+select 'form' as component, 'Create a new Group' as title, 'Create' as validate;
+select 'Name' as name;
+
+insert into groups(name) select :Name where :Name is not null;
+
+select 'list' as component, 'Groups' as title, 'No group yet' as empty_title;
+select name as title from groups;
+
+select 'form' as component, 'Add a user' as title, 'Add' as validate;
+select 'UserName' as name, 'Name' as label;
+select 
+    'Memberships[]'  as name,
+    'Group memberships' as label,
+    'select' as type,
+    1     as multiple,
+    'press ctrl to select multiple values' as description,
+    (
+        SELECT name as label, id as value
+        FROM groups
+        FOR JSON PATH -- this builds a JSON array of objects
+    ) as options;
+
+insert into users(name) select :UserName where :UserName is not null;
+
+insert into group_members(group_id, user_id)
+select json_elem.value, IDENT_CURRENT('users')
+from openjson(:Memberships) as json_elem
+where :Memberships is not null;
+
+select 'list' as component, 'Users' as title, 'No user yet' as empty_title;
+select
+    users.name as title,
+    string_agg(groups.name, ', ') as description
+from users
+left join group_members on users.id = group_members.user_id
+left join groups on groups.id = group_members.group_id
+group by users.id, users.name;

examples/microsoft sql server advanced forms/index.sql

@@ -0,0 +1,35 @@
+create table users (
+    id int primary key IDENTITY(1,1),
+    name varchar(255) not null
+);
+
+create table groups (
+    id int primary key IDENTITY(1,1),
+    name varchar(255) not null
+);
+
+create table group_members (
+    group_id int not null,
+    user_id int not null,
+    constraint PK_group_members primary key (group_id, user_id),
+    constraint FK_group_members_groups foreign key (group_id) references groups (id),
+    constraint FK_group_members_users foreign key (user_id) references users (id)
+);
+
+CREATE TABLE questions(
+    id INT PRIMARY KEY IDENTITY(1,1),
+    question_text TEXT
+);
+
+CREATE TABLE survey_answers(
+    id INT PRIMARY KEY IDENTITY(1,1),
+    question_id INT,
+    answer TEXT,
+    timestamp DATETIME DEFAULT GETDATE(),
+    CONSTRAINT FK_survey_answers_questions FOREIGN KEY (question_id) REFERENCES questions(id)
+);
+
+INSERT INTO questions(question_text) VALUES
+    ('What is your name?'),
+    ('What is your age?'),
+    ('What is your favorite color?');

examples/microsoft sql server advanced forms/screenshots/app.png

@@ -0,0 +1,11 @@
+# Migrations for Microsoft SQL Server
+
+This folder contains the migrations for the Microsoft SQL Server example.
+
+At the time of writing, SQLPage does not support applying migrations for Microsoft SQL Server
+automatically, so we need to apply them manually.
+
+We write the migrations in a folder called `mssql-migrations`, instead of the usual `migrations`
+folder, and we use the `sqlcmd` tool to apply them.
+
+See [how it is done in the docker-compose file](../../docker-compose.yml).

examples/microsoft sql server advanced forms/sqlpage/mssql-migrations/0001_db_init.sql

@@ -0,0 +1,27 @@
+SELECT 'form' as component, 'Survey' as title;
+SELECT id as name, question_text as label, 'textarea' as type
+FROM questions;
+
+-- Save all the answers to the database, whatever the number and id of the questions
+INSERT INTO survey_answers (question_id, answer)
+SELECT
+    question_id,
+    json_unquote(
+        json_extract(
+            sqlpage.variables('post'),
+            concat('$."', question_id, '"')
+        )
+    )
+FROM json_table(
+    json_keys(sqlpage.variables('post')),
+    '$[*]' columns (question_id int path '$')
+) as question_ids;
+
+-- Show the answers
+select 'card' as component, 'Survey results' as title;
+select
+    questions.question_text as title,
+    survey_answers.answer as description,
+    'On ' || survey_answers.timestamp as footer
+from survey_answers
+inner join questions on questions.id = survey_answers.question_id;