From 7011c508e8bdbe12835e069c7e4e01b19ea632c2 Mon Sep 17 00:00:00 2001
From: Daniel Cohen Gindi <danielgindi@gmail.com>
Date: Wed, 3 Feb 2016 13:32:37 +0200
Subject: [PATCH] Added CountDistinct phrase

---
 .../Sql/Phrases/Quantitative/CountDistinct.cs | 58 +++++++++++++++++++
 dg.Sql/dg.Sql.csproj                          |  1 +
 2 files changed, 59 insertions(+)
 create mode 100644 dg.Sql/Sql/Phrases/Quantitative/CountDistinct.cs

diff --git a/dg.Sql/Sql/Phrases/Quantitative/CountDistinct.cs b/dg.Sql/Sql/Phrases/Quantitative/CountDistinct.cs
new file mode 100644
index 00000000..8a74a18e
--- /dev/null
+++ b/dg.Sql/Sql/Phrases/Quantitative/CountDistinct.cs
@@ -0,0 +1,58 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+using dg.Sql.Connector;
+
+namespace dg.Sql.Phrases
+{
+    public class CountDistinct : IPhrase
+    {
+        string TableName;
+        object Object;
+        ValueObjectType ObjectType;
+        
+        public CountDistinct(string tableName, string columnName)
+        {
+            this.TableName = tableName;
+            this.Object = columnName;
+            this.ObjectType = ValueObjectType.ColumnName;
+        }
+
+        public CountDistinct(string columnName)
+            : this(null, columnName)
+        {
+        }
+
+        public CountDistinct(object theObject, ValueObjectType objectType)
+        {
+            this.Object = theObject;
+            this.ObjectType = objectType;
+        }
+
+        public string BuildPhrase(ConnectorBase conn)
+        {
+            string ret;
+
+            ret = @"COUNT(DISTINCT ";
+
+            if (ObjectType == ValueObjectType.ColumnName)
+            {
+                if (TableName != null && TableName.Length > 0)
+                {
+                    ret += conn.EncloseFieldName(TableName);
+                    ret += ".";
+                }
+                ret += conn.EncloseFieldName(Object.ToString());
+            }
+            else if (ObjectType == ValueObjectType.Value)
+            {
+                ret += conn.PrepareValue(Object);
+            }
+            else ret += Object;
+
+            ret += ")";
+
+            return ret;
+        }
+    }
+}
diff --git a/dg.Sql/dg.Sql.csproj b/dg.Sql/dg.Sql.csproj
index 70564cd1..1599c86e 100644
--- a/dg.Sql/dg.Sql.csproj
+++ b/dg.Sql/dg.Sql.csproj
@@ -84,6 +84,7 @@
     <Compile Include="Sql\Phrases\Math\Round.cs" />
     <Compile Include="Sql\Phrases\Quantitative\Avg.cs" />
     <Compile Include="Sql\Phrases\Quantitative\Aggregate.cs" />
+    <Compile Include="Sql\Phrases\Quantitative\CountDistinct.cs" />
     <Compile Include="Sql\Phrases\Quantitative\StandardDeviationOfPopulation.cs" />
     <Compile Include="Sql\Phrases\Quantitative\StandardDeviationOfSample.cs" />
     <Compile Include="Sql\Phrases\Quantitative\StandardVarianceOfSample.cs" />