SNOW 1461701: Add test for Max LOB size parameter switch (#989)

Snowflake.Data.Tests/IntegrationTests/MaxLobSizeIT.cs

@@ -26,7 +26,6 @@ class MaxLobSizeIT : SFBaseTest
         private const int LargeSize = (MaxLobSize / 2);
         private const int MediumSize = (LargeSize / 2);
         private const int OriginSize = (MediumSize / 2);
-        private const int SmallSize = 16;
         private const int LobRandomRange = 100000 + 1; // range to use for generating random numbers (0 - 100000)
 
         private static string s_outputDirectory;
@@ -82,7 +81,7 @@ public void SetUp()
                 using (var command = conn.CreateCommand())
                 {
                     // Create temp table
-                    var columnNamesWithTypes = $"{s_colName[0]} VARCHAR, {s_colName[1]} VARCHAR, {s_colName[2]} INT";
+                    var columnNamesWithTypes = $"{s_colName[0]} VARCHAR({MaxLobSize}), {s_colName[1]} VARCHAR({MaxLobSize}), {s_colName[2]} INT";
                     command.CommandText = $"CREATE OR REPLACE TABLE {t_tableName} ({columnNamesWithTypes})";
                     command.ExecuteNonQuery();
                 }
@@ -273,7 +272,7 @@ public void TestPutGetCommand(int lobSize)
             var c1 = GenerateRandomString(lobSize);
             var c2 = GenerateRandomString(lobSize);
             var c3 = new Random().Next(LobRandomRange);
-            t_colData = new string[]{ c1, c2, c3.ToString() };
+            t_colData = new string[] { c1, c2, c3.ToString() };
 
             PrepareTest();
 
@@ -290,7 +289,6 @@ public void TestPutGetCommand(int lobSize)
 
         static IEnumerable<int> LobSizeTestCases = new[]
         {
-            SmallSize,
             OriginSize,
             MediumSize,
             LargeSize,
@@ -388,6 +386,8 @@ private void AlterSessionSettings(SnowflakeDbConnection conn)
                 //// Alter session max lob
                 //command.CommandText = "ALTER SESSION SET FEATURE_INCREASED_MAX_LOB_SIZE_IN_MEMORY = 'ENABLED'";
                 //command.ExecuteNonQuery();
+                //command.CommandText = "alter session set ALLOW_LARGE_LOBS_IN_EXTERNAL_SCAN = true";
+                //command.ExecuteNonQuery();
             }
         }
 

Snowflake.Data.Tests/IntegrationTests/SFMaxLobSizeSwitchIT.cs

@@ -0,0 +1,35 @@
+using System.Data;
+using NUnit.Framework;
+using Snowflake.Data.Client;
+
+namespace Snowflake.Data.Tests.IntegrationTests
+{
+    [TestFixture]
+    public class SFMaxLobSizeSwitchIT : SFBaseTest
+    {
+        private const string SqlSelectLargeString = "select randstr(20000000, random()) as large_str";
+
+        [Test]
+        [Ignore("TODO: Enable when Max LOB size is available on the automated tests environment")]
+        public void TestIncreaseMaxLobSizeParameterSwitchSelect()
+        {
+            using (var conn = new SnowflakeDbConnection(ConnectionString + "poolingEnabled=false"))
+            {
+                conn.Open();
+                IDbCommand cmd = conn.CreateCommand();
+                cmd.CommandText = "alter session set ENABLE_LARGE_VARCHAR_AND_BINARY_IN_RESULT=false";
+                cmd.ExecuteNonQuery();
+
+                cmd.CommandText = SqlSelectLargeString;
+                var thrown = Assert.Throws<SnowflakeDbException>(() => cmd.ExecuteReader());
+                Assert.That(thrown.Message, Does.Contain("exceeds supported length"));
+
+                cmd.CommandText = "alter session set ENABLE_LARGE_VARCHAR_AND_BINARY_IN_RESULT=true";
+                cmd.ExecuteNonQuery();
+                cmd.CommandText = SqlSelectLargeString;
+                var reader = cmd.ExecuteReader();
+                Assert.IsTrue(reader.Read());
+            }
+        }
+    }
+}