[Improvement-18056] Clean up unused methods and classes in the dolphinschudler-dao-plugin module (#18156)

Author: njnu-seafish

dolphinscheduler-dao-plugin/dolphinscheduler-dao-api/src/main/java/org/apache/dolphinscheduler/dao/plugin/api/dialect/DatabaseDialect.java

@@ -21,6 +21,4 @@ public interface DatabaseDialect {
 
     boolean tableExists(String tableName);
 
-    boolean columnExists(String tableName, String columnName);
-
 }

dolphinscheduler-dao-plugin/dolphinscheduler-dao-h2/src/main/java/org/apache/dolphinscheduler/dao/plugin/h2/dialect/H2Dialect.java

@@ -26,8 +26,4 @@ public boolean tableExists(String tableName) {
         throw new UnsupportedOperationException();
     }
 
-    @Override
-    public boolean columnExists(String tableName, String columnName) {
-        throw new UnsupportedOperationException();
-    }
 }

dolphinscheduler-dao-plugin/dolphinscheduler-dao-mysql/src/main/java/org/apache/dolphinscheduler/dao/plugin/mysql/dialect/MysqlDialect.java

@@ -44,15 +44,4 @@ public boolean tableExists(String tableName) {
         }
     }
 
-    @SneakyThrows
-    @Override
-    public boolean columnExists(String tableName, String columnName) {
-        try (
-                Connection conn = dataSource.getConnection();
-                ResultSet rs =
-                        conn.getMetaData().getColumns(conn.getCatalog(), conn.getSchema(), tableName, columnName)) {
-            return rs.next();
-
-        }
-    }
 }

dolphinscheduler-dao-plugin/dolphinscheduler-dao-postgresql/src/main/java/org/apache/dolphinscheduler/dao/plugin/postgresql/dialect/PostgresqlDialect.java

@@ -46,16 +46,6 @@ public boolean tableExists(String tableName) {
         }
     }
 
-    @SneakyThrows
-    @Override
-    public boolean columnExists(String tableName, String columnName) {
-        try (
-                Connection conn = dataSource.getConnection();
-                ResultSet rs = conn.getMetaData().getTables(conn.getCatalog(), getSchema(), tableName, null)) {
-            return rs.next();
-        }
-    }
-
     private String getSchema() throws SQLException {
         try (
                 Connection conn = dataSource.getConnection();