/// <summary>
/// Builds and finalizes the SQL statement
/// </summary>
/// <param name="sb">StringBuilder that contains the final SQL statement</param>
/// <param name="args">SQL statement parameters</param>
/// <param name="lhs">Left hand side SQL statement</param>
private void Build(StringBuilder sb, List<object> args, Sql lhs)
{
if (!String.IsNullOrEmpty(_sql))
{
// --- Add SQL to the string
if (sb.Length > 0)
{
sb.Append("\n");
}
var sql = Database.ProcessParams(_sql, _args, args);
if (Is(lhs, "WHERE ") && Is(this, "WHERE "))
sql = "AND " + sql.Substring(6);
if (Is(lhs, "ORDER BY ") && Is(this, "ORDER BY "))
sql = ", " + sql.Substring(9);
sb.Append(sql);
}
// Now do rhs
if (_rhs != null)
_rhs.Build(sb, args, this);
}
/// <summary>
/// Checks if the specified Sql instance is the given clause
/// </summary>
/// <param name="sql">Sql instance</param>
/// <param name="sqltype">SQL clause (e.g. WHERE, ORDER BY, etc.)</param>
/// <returns>True, if the Sql instance is the specified clause; otherwise, false.</returns>
static bool Is(Sql sql, string sqltype)
{
return sql != null && sql._sql != null && sql._sql.StartsWith(sqltype, StringComparison.InvariantCultureIgnoreCase);
}
/// <summary>
/// Creates a new instance using the specified Sql instance
/// </summary>
/// <param name="sql">Sql instance this instance belongs to</param>
public SqlJoinClause(Sql sql)
{
_sql = sql;
}
/// <summary>
/// Appends a new chunk of SQL to the current statement
/// </summary>
/// <param name="sql">Sql object representing the statement to append</param>
/// <returns>The Sql object representing the merged SQL statement</returns>
public Sql Append(Sql sql)
{
_sqlFinal = null;
if (_rhs != null)
{
_rhs.Append(sql);
}
else if (_sql != null)
{
_rhs = sql;
}
else
{
_sql = sql._sql;
_args = sql._args;
_rhs = sql._rhs;
}
return this;
}
