/// <summary>
        /// Creates a CREATE INDEX DDL for the specified table and index schema.
        /// </summary>
        /// <param name="tableName">The name of the indexed table.</param>
        /// <param name="indexSchema">The schema of the index object</param>
        /// <returns>A CREATE INDEX DDL (SQLite format).</returns>
        private static string BuildCreateIndex(string tableName, IndexSchema indexSchema)
        {
            var sb = new StringBuilder();
            sb.Append("CREATE ");
            if (indexSchema.IsUnique)
            {
                sb.Append("UNIQUE ");
            }
            sb.Append("INDEX [" + tableName + "_" + indexSchema.IndexName + "]\n");
            sb.Append("ON [" + tableName + "]\n");
            sb.Append("(");
            for (int i = 0; i < indexSchema.Columns.Count; i++)
            {
                sb.Append("[" + indexSchema.Columns[i].ColumnName + "]");
                if (!indexSchema.Columns[i].IsAscending)
                {
                    sb.Append(" DESC");
                }
                if (i < indexSchema.Columns.Count - 1)
                {
                    sb.Append(", ");
                }
            }
            sb.Append(")");

            return sb.ToString();
        }
        /// <summary>
        /// Builds an index schema object from the specified components (Read from SQL Server).
        /// </summary>
        /// <param name="indexName">The name of the index</param>
        /// <param name="desc">The description of the index</param>
        /// <param name="keys">Key columns that are part of the index.</param>
        /// <returns>An index schema object that represents our knowledge of the index</returns>
        private IndexSchema BuildIndexSchema(string indexName, string desc, string keys)
        {
            IndexSchema res = new IndexSchema();
            res.IndexName = indexName;

            // Determine if this is a unique index or not.
            string[] descParts = desc.Split(',');
            foreach (string p in descParts)
            {
                if (p.Trim().Contains("unique"))
                {
                    res.IsUnique = true;
                    break;
                }
            }

            // Get all key names and check if they are ASCENDING or DESCENDING
            res.Columns = new List<IndexColumn>();
            string[] keysParts = keys.Split(',');
            foreach (string p in keysParts)
            {
                Match m = _keyRx.Match(p.Trim());
                if (!m.Success)
                {
                    throw new ApplicationException("Illegal key name [" + p + "] in index [" + indexName + "]");
                }

                string key = m.Groups[1].Value;
                IndexColumn ic = new IndexColumn();
                ic.ColumnName = key;
                ic.IsAscending = !m.Groups[2].Success;

                res.Columns.Add(ic);
            }
            return res;
        }