feat(mssql): show precision/scale for decimal/numeric and length for char/nchar/binary

drivers/mssql/mssql.go

@@ -221,6 +221,8 @@ SELECT
   c.name,
   t.name AS type,
   c.max_length,
+  c.precision,
+  c.scale,
   c.is_nullable,
   c.is_identity,
   object_definition(c.default_object_id),
@@ -244,18 +246,20 @@ ORDER BY c.column_id
 			columnName    string
 			dataType      string
 			maxLength     int
+			precision     int
+			scale         int
 			isNullable    bool
 			isIdentity    bool
 			columnDefault sql.NullString
 			columnComment sql.NullString
 		)
-		err = columnRows.Scan(&columnName, &dataType, &maxLength, &isNullable, &isIdentity, &columnDefault, &columnComment)
+		err = columnRows.Scan(&columnName, &dataType, &maxLength, &precision, &scale, &isNullable, &isIdentity, &columnDefault, &columnComment)
 		if err != nil {
 			return nil, nil, errors.WithStack(err)
 		}
 		column := &schema.Column{
 			Name:     columnName,
-			Type:     convertColumnType(dataType, maxLength),
+			Type:     convertColumnType(dataType, maxLength, precision, scale),
 			Nullable: isNullable,
 			Default:  columnDefault,
 			Comment:  columnComment.String,
@@ -661,14 +665,21 @@ func convertTableType(t string) string {
 	}
 }
 
-func convertColumnType(t string, maxLength int) string {
+func convertColumnType(t string, maxLength, precision, scale int) string {
 	switch t {
 	case "varchar":
 		var length = strconv.Itoa(maxLength)
 		if maxLength == -1 {
 			length = "MAX"
 		}
 		return fmt.Sprintf("varchar(%s)", length)
+	case "char", "binary":
+		return fmt.Sprintf("%s(%d)", t, maxLength)
+	case "nchar":
+		//nchar length is 2 byte, return character length
+		return fmt.Sprintf("nchar(%d)", maxLength/2)
+	case "decimal", "numeric":
+		return fmt.Sprintf("%s(%d,%d)", t, precision, scale)
 	case "nvarchar":
 		//nvarchar length is 2 byte, return character length
 		var length = strconv.Itoa(maxLength / 2)

drivers/mssql/mssql_test.go

@@ -476,3 +476,51 @@ func TestObjectExists(t *testing.T) {
 		t.Error("got true for a dropped table, want false")
 	}
 }
+
+func TestColumnTypePrecisionAndScale(t *testing.T) {
+	const name = "tbls_column_types"
+	if _, err := db.Exec(`DROP TABLE IF EXISTS ` + name); err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() {
+		_, _ = db.Exec(`DROP TABLE IF EXISTS ` + name)
+	})
+	// d_default has no explicit precision, so SQL Server applies decimal(18,0);
+	// it checks that the values come from sys.columns, not the DDL text.
+	if _, err := db.Exec(`CREATE TABLE ` + name + ` (
+  d decimal(9,2),
+  n numeric(18,4),
+  d_default decimal,
+  c char(5),
+  nc nchar(5),
+  b binary(16)
+)`); err != nil {
+		t.Fatal(err)
+	}
+
+	driver := New(db)
+	sc := &schema.Schema{Name: "mssqltestdb"}
+	if err := driver.Analyze(sc); err != nil {
+		t.Fatal(err)
+	}
+
+	tbl, err := sc.FindTableByName(name)
+	if err != nil {
+		t.Fatal(err)
+	}
+	got := map[string]string{}
+	for _, c := range tbl.Columns {
+		got[c.Name] = c.Type
+	}
+	want := map[string]string{
+		"d":         "decimal(9,2)",
+		"n":         "numeric(18,4)",
+		"d_default": "decimal(18,0)",
+		"c":         "char(5)",
+		"nc":        "nchar(5)",
+		"b":         "binary(16)",
+	}
+	if diff := cmp.Diff(want, got); diff != "" {
+		t.Errorf("column types mismatch (-want +got):\n%s", diff)
+	}
+}

sample/azuresql/order_items.md

@@ -8,7 +8,7 @@
 | order_id | int |  | false |  | [orders](orders.md) |  |
 | product_id | int |  | false |  | [products](products.md) |  |
 | quantity | int |  | false |  |  |  |
-| unit_price | decimal |  | false |  |  |  |
+| unit_price | decimal(10,2) |  | false |  |  |  |
 | created | date |  | false |  |  |  |
 
 ## Constraints

sample/azuresql/order_summary.md

@@ -21,7 +21,7 @@ CREATE VIEW order_summary AS (
 | ---- | ---- | ------- | -------- | -------- | ------- | ------- |
 | id | int |  | false |  |  |  |
 | username | varchar(50) |  | true |  |  |  |
-| total_amount | decimal |  | false |  |  |  |
+| total_amount | decimal(12,2) |  | false |  |  |  |
 | status | varchar(20) |  | false |  |  |  |
 | created | date |  | false |  |  |  |
 

sample/azuresql/orders.md

@@ -10,7 +10,7 @@ Customer orders
 | ---- | ---- | ------- | -------- | -------- | ------- | ------- |
 | id | int |  | false | [order_items](order_items.md) |  |  |
 | user_id | int |  | false |  | [users](users.md) |  |
-| total_amount | decimal |  | false |  |  |  |
+| total_amount | decimal(12,2) |  | false |  |  |  |
 | status | varchar(20) | ('pending') | false |  |  | pending/processing/shipped/delivered |
 | created | date |  | false |  |  |  |
 | updated | date |  | true |  |  |  |

sample/azuresql/products.md

@@ -10,7 +10,7 @@ Product catalog
 | ---- | ---- | ------- | -------- | -------- | ------- | ------- |
 | id | int |  | false | [order_items](order_items.md) |  |  |
 | name | nvarchar(255) |  | false |  |  |  |
-| price | decimal |  | false |  |  | Unit price in USD |
+| price | decimal(10,2) |  | false |  |  | Unit price in USD |
 | stock_quantity | int | ((0)) | false |  |  |  |
 | created | date |  | false |  |  |  |
 

sample/azuresql/schema.json

@@ -175,7 +175,7 @@
         },
         {
           "name": "price",
-          "type": "decimal",
+          "type": "decimal(10,2)",
           "nullable": false,
           "comment": "Unit price in USD"
         },
@@ -230,7 +230,7 @@
         },
         {
           "name": "total_amount",
-          "type": "decimal",
+          "type": "decimal(12,2)",
           "nullable": false
         },
         {
@@ -312,7 +312,7 @@
         },
         {
           "name": "unit_price",
-          "type": "decimal",
+          "type": "decimal(10,2)",
           "nullable": false
         },
         {
@@ -419,7 +419,7 @@
         },
         {
           "name": "total_amount",
-          "type": "decimal",
+          "type": "decimal(12,2)",
           "nullable": false
         },
         {
@@ -496,7 +496,7 @@
   ],
   "driver": {
     "name": "sqlserver",
-    "database_version": "Microsoft Azure SQL Edge Developer (RTM) - 15.0.2000.1574 (ARM64) \n\tJan 25 2023 10:36:08 \n\tCopyright (C) 2019 Microsoft Corporation\n\tLinux (Ubuntu 18.04.6 LTS aarch64) \u003cARM64\u003e",
+    "database_version": "Microsoft SQL Server 2019 (RTM-CU32-GDR) (KB5128494) - 15.0.4500.2 (X64) \n\tSep 26 2026 20:15:06 \n\tCopyright (C) 2019 Microsoft Corporation\n\tDeveloper Edition (64-bit) on Linux (Ubuntu 20.04.6 LTS) \u003cX64\u003e",
     "meta": {
       "dict": {
         "Functions": "Stored procedures and functions"