2026-03-12 20:23:15

my/hist_cross_freq.sql

@@ -0,0 +1,43 @@
+set verify off
+
+col value head 'Value'
+col f1 format 999,999,999 head 'Table #1 | frequency'
+col f2 format 999,999,999 head 'Table #2 | frequency'
+column product format 999,999,999 head 'Tables join  | frequency | (product)'
+
+
+break on report skip 1
+compute sum of product on report
+
+WITH f1
+AS (
+	SELECT endpoint_value value
+		,endpoint_number - lag(endpoint_number, 1, 0) OVER (
+			ORDER BY endpoint_number
+			) frequency
+	FROM dba_tab_histograms
+	WHERE OWNER = '&1'
+		AND table_name = '&2'
+		AND column_name = '&3'
+	ORDER BY endpoint_value
+	)
+	,f2
+AS (
+	SELECT endpoint_value value
+		,endpoint_number - lag(endpoint_number, 1, 0) OVER (
+			ORDER BY endpoint_number
+			) frequency
+	FROM dba_tab_histograms
+	WHERE OWNER = '&4'
+		AND table_name = '&5'
+		AND column_name = '&6'
+	ORDER BY endpoint_value
+	)
+SELECT f1.value
+	,f1.frequency f1
+	,f2.frequency f2
+	,f1.frequency * f2.frequency product
+FROM f1
+	,f2
+WHERE f2.value = f1.value;
+