public static QuerySet <T> FromNothing <T>(Expression <Func <object, T> > Selector)
{
var ret = new QuerySet <T>();
var Params = new List <object>();
ret.fields = SelectorCompiler.GetFields(Selector.Body, new string[] { }, new string[] { }, Selector.Parameters, ref Params);
ret.isFromNothing = true;
ret.Params.AddRange(Params);
return(ret);
}
/// <summary>
/// Select clause
/// </summary>
/// <typeparam name="T2"></typeparam>
/// <param name="selector">Example:p=>new {p.Code,p.Name,FullName=p.Code+" "+p.FirstName}</param>
/// <returns></returns>
public QuerySet <T2> Select <T2>(Expression <Func <T, T2> > selector)
{
var ret = this.Clone <T2>();
var Params = this.Params;
var tbls = this.table_names;
if (!string.IsNullOrEmpty(this.table_name))
{
tbls = new string[] { this.table_name };
}
var selectFields = SelectorCompiler.GetFields(selector.Body, new string[] { ret.Schema }, tbls, selector.Parameters, ref Params);
ret.Params = Params;
ret.fields.Clear();
ret.fields.AddRange(selectFields);
return(ret);
}
public QuerySet <T> GroupBy(Expression <Func <T, object> > GroupFields)
{
var ret = this.Clone <T>();
var fieldBody = ((LambdaExpression)GroupFields).Body;
var ParamList = ret.Params;
var x = GroupFields.Parameters[0].Type == typeof(T);
var tableNames = new List <string>();
if (this.table_names != null)
{
tableNames.AddRange(this.table_names);
}
if (!string.IsNullOrEmpty(this.table_name))
{
tableNames.Add(this.table_name);
}
var groupFieldsList = SelectorCompiler.GetFields(fieldBody, new string[] { ret.Schema }, tableNames.ToArray(), GroupFields.Parameters.Cast <ParameterExpression>().ToList(), ref ParamList);
ret.groupbyList.AddRange(groupFieldsList);
return(ret);
}
private static QuerySet <T> BuilJoin <T1, T2, T>(QuerySet <T1> qr1, QuerySet <T2> qr2, Expression <Func <T1, T2, bool> > JoinClause, Expression <Func <T1, T2, T> > selecttor, string JoinType)
{
var q1 = qr1 as QuerySet <T1>;
var q2 = qr2 as QuerySet <T2>;
if (q1.IsSubQuery())
{
}
if (q2.IsSubQuery())
{
}
var ret = new QuerySet <T>();
ret.joinTimes = (q1.joinTimes + 1) * 10 + q2.joinTimes;
var ltName = "l" + ret.joinTimes.ToString();
var rtName = "r" + ret.joinTimes.ToString();
var Params = new List <object>();
Params.AddRange(q1.Params);
Params.AddRange(q2.Params);
var joinParams = new List <object>();
var strJoin = Joinner.GetJoinExpr(JoinClause.Body, new string[] { null, null }, new string[] { ltName, rtName }, JoinClause.Parameters, ref joinParams);
strJoin = utils.RepairParameters(strJoin, Params, joinParams);
Params.AddRange(joinParams);
var leftSource = (!q1.IsSubQuery())? utils.GetSource(q1):"(" + q1.ToSQLString() + ")";
var rightSource = (!q2.IsSubQuery()) ? utils.GetSource(q2) : "(" + q2.ToSQLString() + ")";
rightSource = utils.RepairParameters(rightSource, q1.Params, q2.Params);
ret.datasource = leftSource + " as " + Globals.Compiler.GetQName("", ltName) +
" " + JoinType + " join " + rightSource + " as " + Globals.Compiler.GetQName("", rtName) + " on " + strJoin;
var refTables = new List <string>();
var refParameters = new List <ParameterExpression>();
if (q1.table_names != null)
{
refTables.AddRange(q1.table_names);
}
if (q2.table_names != null)
{
refTables.AddRange(q2.table_names);
}
refTables.Add(ltName);
refTables.Add(rtName);
if (q1.fieldParams != null)
{
refParameters.AddRange(q1.fieldParams);
}
if (q2.fieldParams != null)
{
refParameters.AddRange(q2.fieldParams);
}
refParameters.AddRange(selecttor.Parameters);
var retFields = SelectorCompiler.GetFields(selecttor.Body, new string[] { null, null }, refTables.ToArray(), refParameters.ToArray(), ref Params);
ret.fields = retFields;
ret.fieldParams = new List <ParameterExpression>();
ret.fieldParams.AddRange(refParameters);
ret.parametersExpr = selecttor.Parameters;
ret.Params = Params;
ret.table_names = refTables.ToArray();
return(ret);
}
