Return Accurate Number of Databases

libs/server/Resp/ArrayCommands.cs

@@ -4,8 +4,6 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics;
-using System.Linq;
-using System.Runtime.CompilerServices;
 using Garnet.common;
 using Tsavorite.core;
 
@@ -237,17 +235,17 @@ private bool NetworkSELECT()
                 return true;
             }
 
-            if (storeWrapper.serverOptions.EnableCluster)
+            if (index < storeWrapper.databaseNum)
             {
-                // Cluster mode does not allow DBID
-                while (!RespWriteUtils.WriteError(CmdStrings.RESP_ERR_GENERIC_SELECT_CLUSTER_MODE, ref dcurr, dend))
+                while (!RespWriteUtils.WriteDirect(CmdStrings.RESP_OK, ref dcurr, dend))
                     SendAndReset();
             }
             else
             {
-                if (index == 0)
+                if (storeWrapper.serverOptions.EnableCluster)
                 {
-                    while (!RespWriteUtils.WriteDirect(CmdStrings.RESP_OK, ref dcurr, dend))
+                    // Cluster mode does not allow DBID
+                    while (!RespWriteUtils.WriteError(CmdStrings.RESP_ERR_GENERIC_SELECT_CLUSTER_MODE, ref dcurr, dend))
                         SendAndReset();
                 }
                 else

libs/server/ServerConfig.cs

@@ -80,13 +80,19 @@ private bool NetworkCONFIG_GET()
                         ServerConfigType.SAVE => "$4\r\nsave\r\n$0\r\n\r\n"u8,
                         ServerConfigType.APPENDONLY => storeWrapper.serverOptions.EnableAOF ? "$10\r\nappendonly\r\n$3\r\nyes\r\n"u8 : "$10\r\nappendonly\r\n$2\r\nno\r\n"u8,
                         ServerConfigType.SLAVE_READ_ONLY => clusterSession == null || clusterSession.ReadWriteSession ? "$15\r\nslave-read-only\r\n$2\r\nno\r\n"u8 : "$15\r\nslave-read-only\r\n$3\r\nyes\r\n"u8,
-                        ServerConfigType.DATABASES => storeWrapper.serverOptions.EnableCluster ? "$9\r\ndatabases\r\n$1\r\n1\r\n"u8 : "$9\r\ndatabases\r\n$2\r\n16\r\n"u8,
+                        ServerConfigType.DATABASES => GetDatabases(),
                         ServerConfigType.CLUSTER_NODE_TIMEOUT => Encoding.ASCII.GetBytes($"$20\r\ncluster-node-timeout\r\n${storeWrapper.serverOptions.ClusterTimeout.ToString().Length}\r\n{storeWrapper.serverOptions.ClusterTimeout}\r\n"),
                         ServerConfigType.NONE => throw new NotImplementedException(),
                         ServerConfigType.ALL => throw new NotImplementedException(),
                         _ => throw new NotImplementedException()
                     };
 
+                    ReadOnlySpan<byte> GetDatabases()
+                    {
+                        var databases = storeWrapper.databaseNum.ToString();
+                        return Encoding.ASCII.GetBytes($"$9\r\ndatabases\r\n${databases.Length}\r\n{databases}\r\n");
+                    }
+
                     while (!RespWriteUtils.WriteDirect(parameterValue, ref dcurr, dend))
                         SendAndReset();
                 }

libs/server/StoreWrapper.cs

@@ -104,6 +104,11 @@ public sealed class StoreWrapper
 
         public readonly TimeSpan loggingFrequncy;
 
+        /// <summary>
+        /// NOTE: For now we support only a single database
+        /// </summary>
+        public readonly int databaseNum = 1;
+
         /// <summary>
         /// Constructor
         /// </summary>

test/Garnet.test/RespAdminCommandsTests.cs

@@ -598,7 +598,7 @@ public async Task SeFlushDbAndFlushAllTest2([Values(RespCommand.FLUSHALL, RespCo
         [TestCase("save", "")]
         [TestCase("appendonly", "no")]
         [TestCase("slave-read-only", "no")]
-        [TestCase("databases", "16")]
+        [TestCase("databases", "1")]
         [TestCase("cluster-node-timeout", "60")]
         public void SimpleConfigGet(string parameter, string parameterValue)
         {