fix(csharp/src/Drivers): Make AdbcCommandTimeoutProperty to optional

csharp/src/Client/AdbcCommand.cs

@@ -129,16 +129,12 @@ public override CommandType CommandType
 
         /// <summary>
         /// Gets or sets the name of the command timeout property for the underlying ADBC driver.
+        /// When set, <see cref="CommandTimeout"/> will propagate the value to the driver via this property.
+        /// When not set, <see cref="CommandTimeout"/> only stores the value locally.
         /// </summary>
-        public string AdbcCommandTimeoutProperty
+        public string? AdbcCommandTimeoutProperty
         {
-            get
-            {
-                if (string.IsNullOrEmpty(_commandTimeoutProperty))
-                    throw new InvalidOperationException("CommandTimeoutProperty is not set.");
-
-                return _commandTimeoutProperty!;
-            }
+            get => _commandTimeoutProperty;
             set => _commandTimeoutProperty = value;
         }
 
@@ -147,9 +143,11 @@ public override int CommandTimeout
             get => _timeout;
             set
             {
-                // ensures the property exists before setting the CommandTimeout value
-                string property = AdbcCommandTimeoutProperty;
-                _adbcStatement.SetOption(property, value.ToString(CultureInfo.InvariantCulture));
+                // if the driver property is set, propagate the timeout value to the driver
+                if (!string.IsNullOrEmpty(_commandTimeoutProperty))
+                {
+                    _adbcStatement.SetOption(_commandTimeoutProperty!, value.ToString(CultureInfo.InvariantCulture));
+                }
                 _timeout = value;
             }
         }

csharp/test/Apache.Arrow.Adbc.Tests/Client/ClientTests.cs

@@ -221,12 +221,12 @@ internal void TestConnectionStringParsing(ConnectionStringExample connectionStri
 
             if (!string.IsNullOrEmpty(connectionStringExample.CommandTimeoutProperty))
             {
-                Assert.True(cmd.AdbcCommandTimeoutProperty == connectionStringExample.CommandTimeoutProperty);
-                Assert.True(cmd.CommandTimeout == connectionStringExample.CommandTimeout);
+                Assert.Equal(connectionStringExample.CommandTimeoutProperty, cmd.AdbcCommandTimeoutProperty);
+                Assert.Equal(connectionStringExample.CommandTimeout, cmd.CommandTimeout);
             }
             else
             {
-                Assert.Throws<InvalidOperationException>(() => cmd.AdbcCommandTimeoutProperty);
+                Assert.Null(cmd.AdbcCommandTimeoutProperty);
             }
         }
     }