postgresql: change plugin id (#77444)

* postgres: change plugin id

* fixed cue file

* codeowners update

* fixed backend test

public/app/plugins/datasource/grafana-postgresql-datasource/sqlCompletionProvider.ts

@@ -0,0 +1,45 @@
+import {
+  ColumnDefinition,
+  getStandardSQLCompletionProvider,
+  LanguageCompletionProvider,
+  TableDefinition,
+  TableIdentifier,
+} from '@grafana/experimental';
+import { DB, SQLQuery } from 'app/features/plugins/sql/types';
+
+interface CompletionProviderGetterArgs {
+  getColumns: React.MutableRefObject<(t: SQLQuery) => Promise<ColumnDefinition[]>>;
+  getTables: React.MutableRefObject<(d?: string) => Promise<TableDefinition[]>>;
+}
+
+export const getSqlCompletionProvider: (args: CompletionProviderGetterArgs) => LanguageCompletionProvider =
+  ({ getColumns, getTables }) =>
+  (monaco, language) => ({
+    ...(language && getStandardSQLCompletionProvider(monaco, language)),
+    tables: {
+      resolve: async () => {
+        return await getTables.current();
+      },
+    },
+    columns: {
+      resolve: async (t?: TableIdentifier) => {
+        return await getColumns.current({ table: t?.table, refId: 'A' });
+      },
+    },
+  });
+
+export async function fetchColumns(db: DB, q: SQLQuery) {
+  const cols = await db.fields(q);
+  if (cols.length > 0) {
+    return cols.map((c) => {
+      return { name: c.value, type: c.value, description: c.value };
+    });
+  } else {
+    return [];
+  }
+}
+
+export async function fetchTables(db: DB) {
+  const tables = await db.lookup?.();
+  return tables || [];
+}