limited the opt-in to postgresql & mysql only

Author: jerrytfleung

src/Instrumentation/PDO/README.md

@@ -36,26 +36,14 @@ OTEL_PHP_INSTRUMENTATION_PDO_DISTRIBUTE_STATEMENT_TO_LINKED_SPANS=true
 ```
 
 ### SQL Commenter feature
-The [sqlcommenter](https://google.github.io/sqlcommenter/) feature can be enabled using configuration directive:
+The [sqlcommenter](https://google.github.io/sqlcommenter/) feature can be enabled using configuration directive, currently it can be used with `postgresql` and `mysql` drivers.:
 ```
 otel.instrumentation.pdo.sql_commenter = true
 ```
 or environment variable:
 ```shell
 OTEL_PHP_INSTRUMENTATION_PDO_SQL_COMMENTER=true
 ```
-To select which database(s) to opt-in, specify the database(s) using configuration directive:
-
-Valid values are `postgresql`, `mysql`, `sqlite`, `mssql`, `oracle`, `db2`, `other_sql` and `all`.
-
-```
-otel.instrumentation.pdo.sql_commenter.database[]=postgresql
-otel.instrumentation.pdo.sql_commenter.database[]=mysql
-```
-or environment variable:
-```shell
-OTEL_PHP_INSTRUMENTATION_PDO_SQL_COMMENTER_DATABASE=postgresql,mysql
-```
 
 This feature by default will append a SQL comment to the query statement with the information about the code that executed the query.
 The SQL comment can be configured to prepend to the query statement using the following configuration directive:

src/Instrumentation/PDO/src/PDOInstrumentation.php

@@ -23,7 +23,6 @@ class PDOInstrumentation
 {
     public const NAME = 'pdo';
     private const UNDEFINED = 'undefined';
-    private const ALL = 'all';
 
     public static function register(): void
     {
@@ -402,15 +401,6 @@ private static function isSqlCommenterAttributeEnabled(): bool
         return filter_var(get_cfg_var('otel.instrumentation.pdo.sql_commenter.attribute'), FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE) ?? false;
     }
 
-    private static function getSqlCommenterDatabase(): array
-    {
-        if (class_exists('OpenTelemetry\SDK\Common\Configuration\Configuration') && count($values = Configuration::getList('OTEL_PHP_INSTRUMENTATION_PDO_SQL_COMMENTER_DATABASE', [])) > 0) {
-            return $values;
-        }
-
-        return (array) (get_cfg_var('otel.instrumentation.pdo.sql_commenter.database') ?: []);
-    }
-
     private static function addSqlComments(string $query): string
     {
         $comments = [];
@@ -428,8 +418,6 @@ private static function addSqlComments(string $query): string
 
     private static function isSQLCommenterOptInDatabase(string $db) : bool
     {
-        $optInList = self::getSqlCommenterDatabase();
-
-        return in_array(strtolower($db), $optInList) || in_array(self::ALL, $optInList);
+        return $db == "postgresql" || $db == "mysql";
     }
 }