From 723a08e8146b9db31ad45d564331463ff6a7a529 Mon Sep 17 00:00:00 2001
From: javi <qualopec@gmail.com>
Date: Tue, 19 Aug 2014 18:09:27 +0200
Subject: [PATCH] added CDB_Math_mode

---
 NEWS                             |  4 ++++
 scripts-available/CDB_Math.sql   | 26 ++++++++++++++++++++++++++
 scripts-enabled/220-CDB_Math.sql |  1 +
 test/CDB_MathTest.sql            |  4 ++++
 test/CDB_MathTest_expect         |  3 +++
 5 files changed, 38 insertions(+)
 create mode 100644 scripts-available/CDB_Math.sql
 create mode 120000 scripts-enabled/220-CDB_Math.sql
 create mode 100644 test/CDB_MathTest.sql
 create mode 100644 test/CDB_MathTest_expect

diff --git a/NEWS b/NEWS
index d1dc1fc..78594ef 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,7 @@
+0.3.X (2014-XX-XX)
+------------------
+Added CDB_Math_Mode function
+
 0.3.6 (2014-08-11)
 ------------------
 Dummy release to solve some issues with cdb branch/tag
diff --git a/scripts-available/CDB_Math.sql b/scripts-available/CDB_Math.sql
new file mode 100644
index 0000000..44a1888
--- /dev/null
+++ b/scripts-available/CDB_Math.sql
@@ -0,0 +1,26 @@
+-- CartoDB Math SQL functions
+
+
+-- Mode
+-- https://wiki.postgresql.org/wiki/Aggregate_Mode
+
+CREATE OR REPLACE FUNCTION cartodb._CDB_Math_final_mode(anyarray)
+  RETURNS anyelement AS
+$BODY$
+    SELECT a
+    FROM unnest($1) a
+    GROUP BY 1 
+    ORDER BY COUNT(1) DESC, 1
+    LIMIT 1;
+$BODY$
+LANGUAGE 'sql' IMMUTABLE;
+
+DROP AGGREGATE IF EXISTS cartodb.CDB_Math_Mode(anyelement);
+
+CREATE AGGREGATE cartodb.CDB_Math_Mode(anyelement) (
+  SFUNC=array_append,
+  STYPE=anyarray,
+  FINALFUNC=_CDB_Math_final_mode,
+  INITCOND='{}'
+);
+
diff --git a/scripts-enabled/220-CDB_Math.sql b/scripts-enabled/220-CDB_Math.sql
new file mode 120000
index 0000000..613e0d8
--- /dev/null
+++ b/scripts-enabled/220-CDB_Math.sql
@@ -0,0 +1 @@
+../scripts-available/CDB_Math.sql
\ No newline at end of file
diff --git a/test/CDB_MathTest.sql b/test/CDB_MathTest.sql
new file mode 100644
index 0000000..5a6d752
--- /dev/null
+++ b/test/CDB_MathTest.sql
@@ -0,0 +1,4 @@
+
+SELECT cdb_math_mode(a) from unnest(ARRAY[1,2,2,3]) a;
+SELECT cdb_math_mode(a) from unnest(ARRAY[1,2,3]) a;
+SELECT cdb_math_mode(a) from unnest(ARRAY[1]) a;
diff --git a/test/CDB_MathTest_expect b/test/CDB_MathTest_expect
new file mode 100644
index 0000000..afe234b
--- /dev/null
+++ b/test/CDB_MathTest_expect
@@ -0,0 +1,3 @@
+2
+1
+1