# MSSQL Package

Provides utilities for working with Microsoft SQL Server data types and conversions.

## Components

### Type Mapping

Provides bidirectional conversion between canonical types and MSSQL types:

- **CanonicalToMSSQL**: Convert abstract types to MSSQL-specific types
- **MSSQLToCanonical**: Convert MSSQL types to abstract representation

## Type Conversion Tables

### Canonical → MSSQL

| Canonical | MSSQL | Notes |
|-----------|-------|-------|
| int | INT | 32-bit signed integer |
| int64 | BIGINT | 64-bit signed integer |
| int32 | INT | 32-bit signed integer |
| int16 | SMALLINT | 16-bit signed integer |
| int8 | TINYINT | 8-bit unsigned integer |
| bool | BIT | 0 (false) or 1 (true) |
| float32 | REAL | Single precision floating point |
| float64 | FLOAT | Double precision floating point |
| decimal | NUMERIC | Fixed-point decimal number |
| string | NVARCHAR(255) | Unicode variable-length string |
| text | NVARCHAR(MAX) | Unicode large text |
| timestamp | DATETIME2 | Date and time without timezone |
| timestamptz | DATETIMEOFFSET | Date and time with timezone offset |
| uuid | UNIQUEIDENTIFIER | GUID/UUID type |
| bytea | VARBINARY(MAX) | Variable-length binary data |
| date | DATE | Date only |
| time | TIME | Time only |
| json | NVARCHAR(MAX) | Stored as text (MSSQL v2016+) |
| jsonb | NVARCHAR(MAX) | Stored as text (MSSQL v2016+) |

### MSSQL → Canonical

| MSSQL | Canonical | Notes |
|-------|-----------|-------|
| INT, INTEGER | int | Standard integer |
| BIGINT | int64 | Large integer |
| SMALLINT | int16 | Small integer |
| TINYINT | int8 | Tiny integer |
| BIT | bool | Boolean/bit flag |
| REAL | float32 | Single precision |
| FLOAT | float64 | Double precision |
| NUMERIC, DECIMAL | decimal | Exact decimal |
| NVARCHAR, VARCHAR | string | Variable-length string |
| NCHAR, CHAR | string | Fixed-length string |
| DATETIME2 | timestamp | Default timestamp |
| DATETIMEOFFSET | timestamptz | Timestamp with timezone |
| DATE | date | Date only |
| TIME | time | Time only |
| UNIQUEIDENTIFIER | uuid | UUID/GUID |
| VARBINARY, BINARY | bytea | Binary data |
| XML | string | Stored as text |

## Usage

```go
package main

import (
    "fmt"
    "git.warky.dev/wdevs/relspecgo/pkg/mssql"
)

func main() {
    // Convert canonical to MSSQL
    mssqlType := mssql.ConvertCanonicalToMSSQL("int")
    fmt.Println(mssqlType) // Output: INT

    // Convert MSSQL to canonical
    canonicalType := mssql.ConvertMSSQLToCanonical("BIGINT")
    fmt.Println(canonicalType) // Output: int64

    // Handle parameterized types
    canonicalType = mssql.ConvertMSSQLToCanonical("NVARCHAR(255)")
    fmt.Println(canonicalType) // Output: string
}
```

## Testing

Run tests with:
```bash
go test ./pkg/mssql/...
```

## Notes

- Type conversions are case-insensitive
- Parameterized types (e.g., `NVARCHAR(255)`) have their base type extracted
- Unmapped types default to `string` for safety
- The package supports SQL Server 2016 and later versions