feat: update .

README.md

@@ -1,47 +1,46 @@
-# SQL Database Module
+# azure_tf_sql_database
 
-Creates an Azure SQL Server and Database with a firewall rule allowing Azure services.
+Terraform module that provisions an Azure SQL Server, a SQL Database, and a
+firewall rule allowing Azure services.
 
-## Usage
+## Features
+
+- Azure SQL Server (TLS 1.2 minimum)
+- Azure SQL Database with configurable SKU and size
+- Firewall rule allowing Azure services
+- **Long-Term Retention (LTR) policy** — retains monthly backups for 13 months by default
+
+## Long-Term Retention Policy
+
+The module configures an LTR policy on the `azurerm_mssql_database` resource.
+By default, monthly backups are retained for **13 months** (`P13M`), satisfying
+common long-term data retention requirements (e.g., year-over-year reporting).
+
+Durations use ISO 8601 format:
+
+| Variable                 | Default | Meaning                                  |
+|--------------------------|---------|------------------------------------------|
+| `ltr_weekly_retention`   | `PT0S`  | Weekly backup retention (disabled)       |
+| `ltr_monthly_retention`  | `P13M`  | Monthly backup retention (13 months)     |
+| `ltr_yearly_retention`   | `PT0S`  | Yearly backup retention (disabled)       |
+| `ltr_week_of_year`       | `1`     | Week-of-year for yearly backup (1-52)    |
+
+To override, e.g. to also keep 5 yearly backups:
 
 ```hcl
 module "sql" {
-  source = "./modules/sql_database"
-
-  server_name         = "my-sql-server-123"
-  database_name       = "mydb"
-  resource_group_name = "se-rg"
-  location            = "eastus"
-  admin_login         = "sqladmin"
-  admin_password      = "P@ssw0rd1234!"
-  sku_name            = "Basic"
-
-  tags = {
-    environment = "workshop"
-  }
+  source = "./azure_tf_sql_database"
+  # ...
+  ltr_monthly_retention = "P13M"
+  ltr_yearly_retention  = "P5Y"
+  ltr_week_of_year      = 1
 }
 ```
 
 ## Inputs
 
-| Name | Description | Type | Default | Required |
-|------|-------------|------|---------|----------|
-| server_name | SQL server name (globally unique) | string | — | yes |
-| database_name | Database name | string | — | yes |
-| resource_group_name | Resource group name | string | — | yes |
-| location | Azure region | string | — | yes |
-| admin_login | SQL admin username | string | — | yes |
-| admin_password | SQL admin password | string | — | yes |
-| sku_name | Database SKU | string | `Basic` | no |
-| max_size_gb | Max DB size in GB | number | `2` | no |
-| tags | Resource tags | map(string) | `{}` | no |
+See `variables.tf` for the full list of inputs.
 
 ## Outputs
 
-| Name | Description |
-|------|-------------|
-| server_id | SQL server resource ID |
-| server_fqdn | SQL server FQDN |
-| database_id | Database resource ID |
-| database_name | Database name |
-| connection_string | ADO.NET connection string (sensitive) |
+See `outputs.tf` for the full list of outputs.

main.tf

@@ -16,6 +16,13 @@ resource "azurerm_mssql_database" "this" {
   sku_name    = var.sku_name
   max_size_gb = var.max_size_gb
 
+  long_term_retention_policy {
+    weekly_retention  = var.ltr_weekly_retention
+    monthly_retention = var.ltr_monthly_retention
+    yearly_retention  = var.ltr_yearly_retention
+    week_of_year      = var.ltr_week_of_year
+  }
+
   tags = var.tags
 }
 

variables.tf

@@ -49,3 +49,30 @@ variable "tags" {
   type        = map(string)
   default     = {}
 }
+
+# --- Long-Term Retention (LTR) policy ---
+# Default policy retains monthly backups for 13 months to satisfy long-term
+# data retention requirements. ISO 8601 duration format (e.g., P13M = 13 months).
+variable "ltr_weekly_retention" {
+  description = "Weekly LTR retention duration in ISO 8601 format (e.g., P1W). Use PT0S to disable."
+  type        = string
+  default     = "PT0S"
+}
+
+variable "ltr_monthly_retention" {
+  description = "Monthly LTR retention duration in ISO 8601 format. Defaults to 13 months (P13M)."
+  type        = string
+  default     = "P13M"
+}
+
+variable "ltr_yearly_retention" {
+  description = "Yearly LTR retention duration in ISO 8601 format (e.g., P5Y). Use PT0S to disable."
+  type        = string
+  default     = "PT0S"
+}
+
+variable "ltr_week_of_year" {
+  description = "Week of the year (1-52) to take the yearly LTR backup. Required when yearly_retention is set; ignored otherwise."
+  type        = number
+  default     = 1
+}