diff --git a/example/pkg/database/generated_wrapper_mysql.go b/example/pkg/database/generated_wrapper_mysql.go
index f2cf466..9c375b3 100644
--- a/example/pkg/database/generated_wrapper_mysql.go
+++ b/example/pkg/database/generated_wrapper_mysql.go
@@ -59,7 +59,7 @@ func (w *mysqlWrapper) CreateBook(ctx context.Context, arg CreateBookParams) (Bo
 		return Book{}, err
 	}
 
-	id, err := res.LastInsertID()
+	id, err := res.LastInsertId()
 	if err != nil {
 		return Book{}, err
 	}
@@ -89,7 +89,7 @@ func (w *mysqlWrapper) CreateTag(ctx context.Context, name string) (Tag, error)
 		return Tag{}, err
 	}
 
-	id, err := res.LastInsertID()
+	id, err := res.LastInsertId()
 	if err != nil {
 		return Tag{}, err
 	}
diff --git a/generator/helpers.go b/generator/helpers.go
index 86c68af..56b79c1 100644
--- a/generator/helpers.go
+++ b/generator/helpers.go
@@ -92,11 +92,24 @@ func FixAcronyms(content []byte) []byte {
 		// 3. Mid: `([a-z])(Acronym)([A-Z])` - acronym in middle of camelCase, e.g., Id in userIdMore.
 		// 4. End: `([a-z])(Acronym)$` - acronym at end of identifier, e.g., Id in userId.
 		// 5. NonLetter: `([a-z])(Acronym)([^A-Za-z])` - acronym followed by non-letter.
+		//    For Id, we exclude '(' to avoid transforming method calls like LastInsertId().
 		regexStart := regexp.MustCompile(`^(` + a.pattern + `)([A-Z])`)
 		regexAfterUpper := regexp.MustCompile(`([A-Z])(` + a.pattern + `)([A-Z])`)
 		regexMid := regexp.MustCompile(`([a-z])(` + a.pattern + `)([A-Z])`)
 		regexEnd := regexp.MustCompile(`([a-z])(` + a.pattern + `)$`)
-		regexNonLetter := regexp.MustCompile(`([a-z])(` + a.pattern + `)([^A-Za-z])`)
+
+		// For Id, exclude '(' to preserve method calls like res.LastInsertId()
+		// For Url, exclude ':' and ',' to preserve struct field names like NewUrl, OldUrl
+		nonLetterClass := `[^A-Za-z]`
+
+		switch a.pattern {
+		case "Id":
+			nonLetterClass = `[^A-Za-z(]`
+		case "Url":
+			nonLetterClass = `[^A-Za-z:,]`
+		}
+
+		regexNonLetter := regexp.MustCompile(`([a-z])(` + a.pattern + `)(` + nonLetterClass + `)`)
 
 		// Start case: replace with replacement followed by ${2} (the uppercase after).
 		result = regexStart.ReplaceAllString(result, a.replacement+"${2}")
@@ -124,7 +137,7 @@ func writeFile(dir, filename string, content []byte) {
 	// 2. Format with gofumpt
 	formatted, err := format.Source(withImports, format.Options{
 		LangVersion: "",
-		ExtraRules:  true,
+		ExtraRules:  false,
 	})
 	if err != nil {
 		log.Println(string(withImports))
diff --git a/generator/helpers_test.go b/generator/helpers_test.go
index aebbbc2..3a90822 100644
--- a/generator/helpers_test.go
+++ b/generator/helpers_test.go
@@ -109,6 +109,36 @@ func TestFixAcronyms(t *testing.T) {
 			input:    "",
 			expected: "",
 		},
+		{
+			name:     "LastInsertId in method call should not be transformed",
+			input:    "res.LastInsertId()",
+			expected: "res.LastInsertId()",
+		},
+		{
+			name:     "SetId in method call should not be transformed",
+			input:    "obj.SetId(123)",
+			expected: "obj.SetId(123)",
+		},
+		{
+			name:     "userId in variable assignment should become userID",
+			input:    "userId = 123",
+			expected: "userID = 123",
+		},
+		{
+			name:     "NewUrl in struct literal should remain NewUrl",
+			input:    "NewUrl: \"value\"",
+			expected: "NewUrl: \"value\"",
+		},
+		{
+			name:     "OldUrl in struct literal should remain OldUrl",
+			input:    "OldUrl: \"value\"",
+			expected: "OldUrl: \"value\"",
+		},
+		{
+			name:     "profileUrl in assignment should become profileURL",
+			input:    "profileUrl = \"https://example.com\"",
+			expected: "profileURL = \"https://example.com\"",
+		},
 	}
 
 	for _, tt := range tests {