PostgreSQLDialect.cs: Define trigonometric functions. Tests covered by Linq.MathTests. NH-3398.

Author: oskarb

src/NHibernate/Dialect/PostgreSQLDialect.cs

@@ -64,6 +64,21 @@ public PostgreSQLDialect()
 			RegisterFunction("replace", new StandardSQLFunction("replace", NHibernateUtil.String));
 			RegisterFunction("left", new SQLFunctionTemplate(NHibernateUtil.String, "substr(?1,1,?2)"));
 			RegisterFunction("mod", new SQLFunctionTemplate(NHibernateUtil.Int32, "((?1) % (?2))"));
+
+			RegisterFunction("sign", new StandardSQLFunction("sign", NHibernateUtil.Int32));
+			RegisterFunction("round", new SQLFunctionTemplate(NHibernateUtil.Double, "round(cast(?1 as numeric), ?2)"));
+
+			// Trigonometric functions.
+			RegisterFunction("acos", new StandardSQLFunction("acos", NHibernateUtil.Double));
+			RegisterFunction("asin", new StandardSQLFunction("asin", NHibernateUtil.Double));
+			RegisterFunction("atan", new StandardSQLFunction("atan", NHibernateUtil.Double));
+			RegisterFunction("cos", new StandardSQLFunction("cos", NHibernateUtil.Double));
+			RegisterFunction("cot", new StandardSQLFunction("cot", NHibernateUtil.Double));
+			RegisterFunction("sin", new StandardSQLFunction("sin", NHibernateUtil.Double));
+			RegisterFunction("tan", new StandardSQLFunction("tan", NHibernateUtil.Double));
+			RegisterFunction("atan2", new StandardSQLFunction("atan2", NHibernateUtil.Double));
+
+			RegisterFunction("power", new StandardSQLFunction("power", NHibernateUtil.Double));
 		}
 
 		public override string AddColumnString