Merge branch 'master' into cdb_querytables_quoted

Conflicts:
	test/extension/test.sh

scripts-available/CDB_ColumnNames.sql

@@ -3,11 +3,12 @@ CREATE OR REPLACE FUNCTION CDB_ColumnNames(REGCLASS)
 RETURNS SETOF information_schema.sql_identifier
 AS $$
 
-    SELECT column_name 
-      FROM information_schema.columns 
-      WHERE
-        table_name IN (SELECT CDB_UserTables())
-        AND table_name = '' || $1 || '';
+    SELECT c.column_name
+      FROM information_schema.columns c, pg_class _tn, pg_namespace _sn
+      WHERE table_name = _tn.relname
+        AND table_schema = _sn.nspname
+        AND _tn.oid = $1::oid
+        AND _sn.oid = _tn.relnamespace;
          
 $$ LANGUAGE SQL;
 

scripts-available/CDB_ColumnType.sql

@@ -3,12 +3,13 @@ CREATE OR REPLACE FUNCTION CDB_ColumnType(REGCLASS, TEXT)
 RETURNS information_schema.character_data
 AS $$
 
-    SELECT data_type 
-      FROM information_schema.columns 
-      WHERE
-        table_name IN (SELECT CDB_UserTables())
-        AND table_name = '' || $1 || ''
-        AND column_name = '' || quote_ident($2) || '';
+    SELECT c.data_type
+      FROM information_schema.columns c, pg_class _tn, pg_namespace _sn
+      WHERE table_name = _tn.relname
+        AND table_schema = _sn.nspname
+        AND column_name = $2
+        AND _tn.oid = $1::oid
+        AND _sn.oid = _tn.relnamespace;
          
 $$ LANGUAGE SQL;
 

scripts-available/CDB_Stats.sql

@@ -0,0 +1,47 @@
+--
+-- Calculate basic statistics of a given dataset
+--
+-- @param in_array A numeric array of numbers
+--
+-- Returns: statistical quantity chosen
+-- 
+-- References: http://www.itl.nist.gov/div898/handbook/eda/section3/eda35b.htm
+--
+
+-- Calculate kurtosis
+CREATE OR REPLACE FUNCTION CDB_Kurtosis ( in_array NUMERIC[] ) RETURNS NUMERIC as $$
+DECLARE
+    a numeric;
+    c numeric;
+    s numeric;
+    k numeric;
+BEGIN
+    SELECT AVG(e), COUNT(e)::numeric, stddev(e) INTO a, c, s FROM ( SELECT unnest(in_array) e ) x;
+
+    EXECUTE 'SELECT sum(power($1 - e, 4)) / ( $2 * power($3, 4)) - 3
+             FROM (SELECT unnest($4) e ) x'
+    INTO k
+    USING a, c, s, in_array;
+
+    RETURN k;
+END;
+$$ language plpgsql IMMUTABLE;
+
+-- Calculate skewness
+CREATE OR REPLACE FUNCTION CDB_Skewness ( in_array NUMERIC[] ) RETURNS NUMERIC as $$
+DECLARE
+    a numeric;
+    c numeric;
+    s numeric;
+    sk numeric;
+BEGIN
+    SELECT AVG(e), COUNT(e)::numeric, stddev(e) INTO a, c, s FROM ( SELECT unnest(in_array) e ) x;
+
+    EXECUTE 'SELECT sum(power($1 - e, 3)) / ( $2 * power($3, 3))
+             FROM (SELECT unnest($4) e ) x'
+    INTO sk
+    USING a, c, s, in_array;
+
+    RETURN sk;
+END;
+$$ language plpgsql IMMUTABLE;

scripts-enabled/CDB_Stats.sql

@@ -0,0 +1 @@
+../scripts-available/CDB_Stats.sql

test/CDB_StatsTest.sql

@@ -0,0 +1,16 @@
+-- continuous uniform distribution has kurtosis = -6/5, skewness = 0.0
+-- http://mathworld.wolfram.com/UniformDistribution.html
+set client_min_messages to ERROR;
+
+With dist As (
+  SELECT random()::numeric As val
+  FROM generate_series(1,50000) t
+)
+
+SELECT 
+  -- does random dist values match within 1% of known values
+  abs(CDB_Kurtosis(array_agg(val)) + 1.20) < 1e-2 As kurtosis,
+  abs(CDB_Skewness(array_agg(val)) - 0) < 1e-2 As skewness
+FROM dist;
+
+set client_min_messages to NOTICE;

test/CDB_StatsTest_expect

@@ -0,0 +1,3 @@
+SET
+t|t
+SET

test/extension/run_at_cartodb_schema.sql

@@ -1,4 +1,6 @@
 SET SCHEMA 'cartodb';
 \i scripts-available/CDB_Quota.sql
 \i scripts-available/CDB_TableMetadata.sql
+\i scripts-available/CDB_ColumnNames.sql
+\i scripts-available/CDB_ColumnType.sql
 SET SCHEMA 'public';

test/extension/test.sh

@@ -343,6 +343,40 @@ function test_cdb_tablemetadatatouch_fails_from_user_without_permission() {
     sql postgres "REVOKE ALL ON CDB_TableMetadata FROM cdb_testmember_1;"
 }
 
+function test_cdb_column_names() {
+    sql cdb_testmember_1 'CREATE TABLE cdb_testmember_1.table_cnames(c int, a int, r int, t int, o int);'
+    sql cdb_testmember_2 'CREATE TABLE cdb_testmember_2.table_cnames(d int, b int);'
+
+    sql cdb_testmember_1 "SELECT string_agg(c,'') from (SELECT cartodb.CDB_ColumnNames('table_cnames') c) as s" should "carto"
+    sql cdb_testmember_2 "SELECT string_agg(c,'') from (SELECT cartodb.CDB_ColumnNames('table_cnames') c) as s" should "db"
+
+    sql postgres "SELECT string_agg(c,'') from (SELECT cartodb.CDB_ColumnNames('cdb_testmember_1.table_cnames'::regclass) c) as s" should "carto"
+    sql postgres "SELECT string_agg(c,'') from (SELECT cartodb.CDB_ColumnNames('cdb_testmember_2.table_cnames') c) as s" should "db"
+
+    # Using schema from owner
+    sql cdb_testmember_1 "SELECT string_agg(c,'') from (SELECT cartodb.CDB_ColumnNames('cdb_testmember_1.table_cnames') c) as s" should "carto"
+
+    ## it's not possible to get column names from a table where you don't have permissions
+    sql cdb_testmember_2 "SELECT string_agg(c,'') from (SELECT cartodb.CDB_ColumnNames('cdb_testmember_1.table_cnames') c) as s" fails
+
+    sql cdb_testmember_1 'DROP TABLE cdb_testmember_1.table_cnames'
+    sql cdb_testmember_2 'DROP TABLE cdb_testmember_2.table_cnames'
+}
+
+function test_cdb_column_type() {
+    sql cdb_testmember_1 'CREATE TABLE cdb_testmember_1.table_ctype(c int, a int, r int, t int, o int);'
+    sql cdb_testmember_2 'CREATE TABLE cdb_testmember_2.table_ctype(c text, a text, r text, t text, o text);'
+
+    sql cdb_testmember_1 "SELECT cartodb.CDB_ColumnType('table_ctype', 'c')" should "integer"
+    sql cdb_testmember_2 "SELECT cartodb.CDB_ColumnType('table_ctype', 'c')" should "text"
+
+    sql postgres "SELECT cartodb.CDB_ColumnType('cdb_testmember_1.table_ctype', 'c')" should "integer"
+    sql postgres "SELECT cartodb.CDB_ColumnType('cdb_testmember_2.table_ctype', 'c')" should "text"
+
+    sql cdb_testmember_1 'DROP TABLE cdb_testmember_1.table_ctype'
+    sql cdb_testmember_2 'DROP TABLE cdb_testmember_2.table_ctype'
+}
+
 function test_cdb_querytables_schema_and_table_names_with_dots() {
     ${CMD} -d ${DATABASE} -f scripts-available/CDB_QueryStatements.sql
     ${CMD} -d ${DATABASE} -f scripts-available/CDB_QueryTables.sql