Materialized Views and refereshing one

Author: ptyadana

Advanced SQL for Query Tuning and Performance Optimization/05.Materialized_Views.sql

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+/************* Materialized Views **************/
+
+/* 
+if we check on Database > specific Database? Schema > Materialized Views >
+there may not be anything if don't have exsisting one.
+*/
+
+-- Create new materialized view
+CREATE MATERIALIZED VIEW mv_staff AS(
+	SELECT s.last_name, s.department, s.job_title, cr.company_regions
+	FROM staff s
+	JOIN company_regions cr ON cr.region_id = s.region_id
+);
+
+
+-- get data from materialized view
+SELECT * FROM mv_staff LIMIT 10;
+
+
+------------- Limitation of Materialized Views -----------
+/*
+If there is any changes to source table (in this case staff and company_regions),
+our materialzed views data won't be refelected automatically. So data will become stale over time.
+Thus, we need to refresh data on materialized view.
+*/
+
+
+------------ Refershing Materialized Views -----------------
+/* 
+this will rebuild the entire table and repopulate the data.
+so we need to consider carefully how often we want to refresh it and may want to space out the frequency.
+*/
+
+REFRESH MATERIALIZED VIEW mv_staff;
+
+
+
+
+
+