Add MSSQL placeholder

placeholder.go

@@ -26,6 +26,10 @@ var (
 	// Colon is a PlaceholderFormat instance that replaces placeholders with
 	// colon-prefixed positional placeholders (e.g. :1, :2, :3).
 	Colon = colonFormat{}
+
+	// Position is a PlaceholderFormat instance that replaces placeholders with
+	// @p-prefixed positional placeholders normally used with MSSQL drivers (e.g @p1, @p2)
+	Position = positionFormat{}
 )
 
 type questionFormat struct{}
@@ -46,6 +50,12 @@ func (colonFormat) ReplacePlaceholders(sql string) (string, error) {
 	return replacePositionalPlaceholders(sql, ":")
 }
 
+type positionFormat struct{}
+
+func (positionFormat) ReplacePlaceholders(sql string) (string, error) {
+	return replacePositionalPlaceholders(sql, "@p")
+}
+
 // Placeholders returns a string with count ? placeholders joined with commas.
 func Placeholders(count int) string {
 	if count < 1 {

placeholder_test.go

@@ -25,6 +25,12 @@ func TestColon(t *testing.T) {
 	assert.Equal(t, "x = :1 AND y = :2", s)
 }
 
+func TestPosition(t *testing.T) {
+	sql := "x = ? AND y = ?"
+	s, _ := Position.ReplacePlaceholders(sql)
+	assert.Equal(t, "x = @p1 AND y = @p2", s)
+}
+
 func TestPlaceholders(t *testing.T) {
 	assert.Equal(t, Placeholders(2), "?,?")
 }