statiq-macros 0.2.2

# Statiq-Macros


**Procedural macros for Statiq — compile-time SQL code generation**

[![Crates.io](https://img.shields.io/crates/v/statiq-macros.svg)](https://crates.io/crates/statiq-macros)
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This crate provides the `#[derive(SqlEntity)]` procedural macro used by [statiq](https://crates.io/crates/statiq) to generate compile-time SQL constants and metadata for MSSQL database operations.

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## 🎯 Purpose


`statiq-macros` is automatically used when you add the `statiq` crate to your project. It:

✅ **Generates SQL at compile time** — `SELECT`, `INSERT`, `UPDATE`, `DELETE` statements as `&'static str`  
✅ **Extracts type information** — Entity structure, column names, primary keys  
✅ **Supports SQL overrides** — `#[sql_column]`, `#[sql_table]` attributes  
✅ **Zero runtime overhead** — All work happens during compilation  

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## 📦 Installation


**You don't need to add this manually.** When you add `statiq` to Cargo.toml, it automatically includes `statiq-macros`:

```toml
[dependencies]
statiq = "0.1"
```

If you need to use the macro directly (rare):

```toml
[dependencies]
statiq-macros = "0.1"

# You'll also need:

statiq = "0.1"
serde = { version = "1", features = ["derive"] }
```

---

## 📖 Usage


The macro is used via `#[derive(SqlEntity)]`:

```rust
use statiq_macros::SqlEntity;

#[derive(SqlEntity, serde::Serialize, serde::Deserialize, Clone)]

#[sql_table("Users", schema = "dbo")]

pub struct User {
    #[sql_primary_key(identity)]
    pub id: i32,

    pub email: String,
    pub name: String,

    #[sql_default]
    pub created_at: chrono::DateTime<chrono::Utc>,

    #[sql_computed]
    pub full_name: Option<String>,

    #[sql_ignore]
    pub temp_field: bool,
}
```

---

## 🏷️ Supported Attributes


### Struct-Level


| Attribute | Example | Purpose |
|---|---|---|
| `#[sql_table(...)]` | `#[sql_table("Users", schema = "dbo")]` | Map struct to database table |

### Field-Level


| Attribute | Purpose | Auto-Included | Auto-Excluded |
|---|---|---|---|
| `#[sql_primary_key]` | Regular primary key | SELECT, UPDATE | INSERT |
| `#[sql_primary_key(identity)]` | IDENTITY column | SELECT, UPDATE | INSERT |
| `#[sql_column("ColumnName")]` | Override SQL column name | - | - |
| `#[sql_default]` | Database default value | SELECT, UPDATE | INSERT |
| `#[sql_computed]` | Computed column | SELECT | INSERT, UPDATE |
| `#[sql_ignore]` | Not mapped to database | - | All SQL operations |

---

## 🔍 Generated SQL Example


For the `User` struct above, the macro generates (conceptually):

```rust
// SELECT
const SQL_SELECT: &str = "SELECT [id], [email], [name], [created_at], [full_name] FROM [dbo].[Users]";
const SQL_SELECT_BY_ID: &str = "SELECT ... WHERE [id] = @id";

// INSERT (excludes id, full_name)
const SQL_INSERT: &str = "INSERT INTO [dbo].[Users] ([email], [name], [created_at]) VALUES (@email, @name, @created_at)";

// UPDATE (excludes id, full_name)
const SQL_UPDATE: &str = "UPDATE [dbo].[Users] SET [email] = @email, [name] = @name, [created_at] = @created_at WHERE [id] = @id";

// DELETE
const SQL_DELETE: &str = "DELETE FROM [dbo].[Users] WHERE [id] = @id";
```

All as compile-time constants — no runtime string building!

---

## 🚀 Why Use statiq-macros?


**Performance**
- Zero reflection overhead
- Static dispatch, no vtables
- SQL statements are compile-time constants

**Type Safety**
- Result sets map directly to Rust structs
- Column name changes caught at compile time
- Invalid SQL caught before runtime

**Developer Experience**
- Single source of truth (your Rust struct)
- No manual SQL strings to maintain
- IDE support for field names

---

## 🔗 See Also


- **[statiq](https://crates.io/crates/statiq)** — Main crate with CRUD operations, connection pooling, caching
- **Docs**: [docs.rs/statiq-macros](https://docs.rs/statiq-macros)
- **GitHub**: [github.com/yasinakmaz/Statiq](https://github.com/yasinakmaz/Statiq)

---

## 📄 License


Licensed under MIT OR Apache-2.0. See [LICENSE](../LICENSE-MIT) and [LICENSE-APACHE](../LICENSE-APACHE).