--- a/postgres.rst	Mon Sep 13 13:35:35 2021 +0300
+++ b/postgres.rst	Mon Sep 13 13:42:01 2021 +0300
@@ -518,6 +518,8 @@
   Database Object Management Functions.
 https://wiki.postgresql.org/wiki/Disk_Usage
   Finding the size of various object in your database.
+https://wiki.postgresql.org/wiki/Count_estimate
+  Count estimate.
 https://wiki.postgresql.org/wiki/Index_Maintenance
   Index size/usage statistics.