CloudWatch: Correctly quote metric names with special characters (#78958)

public/app/plugins/datasource/cloudwatch/language/cloudwatch-sql/SQLGenerator.test.ts

@@ -62,6 +62,13 @@ describe('SQLGenerator', () => {
         `SELECT COUNT("Bytes-Per-Second") FROM SCHEMA("AWS/EC2")`
       );
     });
+
+    it('should wrap in double quotes if metric name starts with a number ', () => {
+      const select = createFunctionWithParameter('COUNT', ['4xxErrorRate']);
+      expect(new SQLGenerator().expressionToSqlQuery({ ...baseQuery, select })).toEqual(
+        `SELECT COUNT("4xxErrorRate") FROM SCHEMA("AWS/EC2")`
+      );
+    });
   });
 
   describe('from', () => {

public/app/plugins/datasource/cloudwatch/language/cloudwatch-sql/SQLGenerator.ts

@@ -146,10 +146,11 @@ export default class SQLGenerator {
   }
 
   private formatValue(label: string): string {
-    const specialCharacters = /[/\s\.-]/; // slash, space, dot or dash
+    const specialCharacters = /[/\s\.%-]/; // slash, space, dot, percent, or dash
+    const startsWithNumber = /^\d/;
 
     const interpolated = this.templateSrv.replace(label, {}, 'raw');
-    if (specialCharacters.test(interpolated)) {
+    if (specialCharacters.test(interpolated) || startsWithNumber.test(interpolated)) {
       return `"${label}"`;
     }