refactor: sql-tools (#19717)

server/src/sql-tools/readers/comment.reader.ts

@@ -0,0 +1,36 @@
+import { DatabaseReader } from 'src/sql-tools/types';
+
+export const readComments: DatabaseReader = async (schema, db) => {
+  const comments = await db
+    .selectFrom('pg_description as d')
+    .innerJoin('pg_class as c', 'd.objoid', 'c.oid')
+    .leftJoin('pg_attribute as a', (join) =>
+      join.onRef('a.attrelid', '=', 'c.oid').onRef('a.attnum', '=', 'd.objsubid'),
+    )
+    .select([
+      'c.relname as object_name',
+      'c.relkind as object_type',
+      'd.description as value',
+      'a.attname as column_name',
+    ])
+    .where('d.description', 'is not', null)
+    .orderBy('object_type')
+    .orderBy('object_name')
+    .execute();
+
+  for (const comment of comments) {
+    if (comment.object_type === 'r') {
+      const table = schema.tables.find((table) => table.name === comment.object_name);
+      if (!table) {
+        continue;
+      }
+
+      if (comment.column_name) {
+        const column = table.columns.find(({ name }) => name === comment.column_name);
+        if (column) {
+          column.comment = comment.value;
+        }
+      }
+    }
+  }
+};