/// <summary>
/// 构造函数
/// </summary>
public SubQuerySqlStatement()
: base()
{
From = new From();
mainFromItem = new FromItem();
From.ChildCollection.Add(mainFromItem);
SelectList = new SelectFieldListStatement();
JoinCondition = new JoinConditionStatement();
FilterCondition = new ConditionStatement();
OrderByCondition = new ConditionStatement();
DictFieldAliasMapping = new Dictionary <string, string>();
}
/// <summary>
/// 根据SQLDOM元素类型初始化SQLDOM元素对象
/// </summary>
/// <param name="sqlElementType">SQLDOM元素类型</param>
/// <returns>SQLDOM元素对象</returns>
public static SqlElement GetSQLElement(int sqlElementType)
{
SqlElement element = null;
SqlElementType type = (SqlElementType)sqlElementType;
switch (type)
{
case SqlElementType.InsertField:
element = new InsertField();
break;
case SqlElementType.SqlPrimaryKeyField:
element = new SqlPrimaryKeyField();
break;
case SqlElementType.SelectListField:
element = new SelectListField();
break;
case SqlElementType.UpdateField:
element = new UpdateField();
break;
case SqlElementType.From:
element = new From();
break;
case SqlElementType.FromItem:
element = new FromItem();
break;
case SqlElementType.JoinCondition:
element = new JoinConditionStatement();
break;
case SqlElementType.OrderByCondition:
element = new ConditionStatement();
break;
case SqlElementType.FilterCondition:
element = new ConditionStatement();
break;
case SqlElementType.UnKnown:
break;
}
return(element);
}
public static ConditionStatement ParseOrderByClauses(List<OrderByClause> orderByClauses, DomainObject domainObject, DataObject dataObject)
{
var orderbyCondition = new ConditionStatement();
if (orderByClauses == null || orderByClauses.Count == 0)
return orderbyCondition;
var list = new List<string>();
foreach (var orderByClause in orderByClauses)
{
var orderByString = ParseOrderByClause(orderByClause, domainObject, dataObject);
if (!string.IsNullOrWhiteSpace(orderByString))
list.Add(orderByString);
}
if (list.Count > 0)
{
orderbyCondition.ConditionString = string.Format("ORDER BY {0}", string.Join(",", list));
}
return orderbyCondition;
}
private static ConditionStatement ParseConditionStatement(FilterClause filterClause, DomainObject domainObject, DataObject dataObject, SqlTable sqlTable)
{
var conditionStatement = new ConditionStatement();
conditionStatement.SetLogicalOperator(filterClause.LogicalOperator);
conditionStatement.ConditionField.Table = sqlTable;
conditionStatement.RelationalOperator = filterClause.RelationalOperator;
conditionStatement.ConditionFieldValue = new ConditionFieldValue()
{
ValueType = filterClause.FilterFieldValue.ValueType,
IsNull = filterClause.FilterFieldValue.IsNull,
Value = filterClause.FilterFieldValue.FiledValue,
};
DataColumn column = null;
DomainObjectElement element = null;
switch (filterClause.FilterField.FieldType)
{
case FieldType.Column:
column = dataObject.Columns.FirstOrDefault(i => i.ColumnName == filterClause.FilterField.Field);
conditionStatement.ConditionField.FieldName = column.ColumnName;
break;
case FieldType.Element:
element = domainObject.Elements.FirstOrDefault(i => i.Name == filterClause.FilterField.Field || i.ID == filterClause.FilterField.Field);
column = dataObject.Columns.FirstOrDefault(i => i.ID == element.DataColumnID);
conditionStatement.ConditionField.FieldName = column.ColumnName;
break;
case FieldType.FunctionExpression:
conditionStatement.IsExpression = true;
conditionStatement.ConditionField.FieldName = filterClause.FilterField.Field;
break;
default:
break;
}
conditionStatement.ConditionFieldValue.ConditionFieldName = column.ColumnName;
return conditionStatement;
}
