public override void AdjustTranslater(ExpressionTranslater translater)
{
var exp = translater.Expression;
if (exp.IsPagable)
{
AdjustPagable(translater);
}
}
protected override void AdjustPagable(ExpressionTranslater translater)
{
var oldSQL = translater.CommandText;
var exp = translater.Expression;
var sql = @"SELECT * FROM ({OLDSQL}) AS tmptableinner WHERE rowId between {N} and {M}";
sql = sql.Replace("{N}", (exp.StartIndex.Value + 1).ToString());
sql = sql.Replace("{M}", (exp.EndIndex.Value + 1).ToString());
sql = sql.Replace("{OLDSQL}", oldSQL);
translater.SetCommandText(sql);
}
/// <summary>
/// 获取Sq语句中 "select" 和 字段之间 的部分
/// 这里针对分页做了处理。如果不是分页检索，那么调用父类的默认实现
/// </summary>
/// <returns></returns>
public override string GetSQLSelectTopClip(ExpressionTranslater translater)
{
StringBuilder str = new StringBuilder();
var exp = translater.Expression;
if (exp.IsPagable)
{
IList <OrderByExpression> orderby = exp.IsOrderBy ? exp.OrderByList : new List <OrderByExpression>()
{
new OrderByExpression(exp.From.GetIdentityField(), OrderByDirection.Asc)
};
str.Append(string.Concat("row_number() over (", translater.TranslateOrderyByList(orderby), ") as rowId,"));
}
else
{
return(base.GetSQLSelectTopClip(translater));
}
return(str.ToString());
}
