public static V MinValue <T, V>(DatabaseCore accessor, string column, Clause clause = null) where T : TableEntity, new()
{
if (accessor == null)
{
return(default(V));
}
var entity = CreateEntity <T>();
var col = entity.FindColumn(column);
if (col == null)
{
return(default(V));
}
var sql = new StringBuilder();
sql.AppendLine(string.Format("SELECT MIN({0}) AS MINVAL FROM [{1}]", col.ID, entity.TableName));
string where = null;
List <DbParameter> parameters = null;
if (clause != null)
{
clause.Export(accessor, out where, out parameters);
}
if (!string.IsNullOrEmpty(where))
{
sql.AppendLine("WHERE");
sql.AppendLine(where);
}
return(accessor.RetrieveValue <V>(accessor.CreateCommand(sql.ToString(), parameters), default(V)));
}
public List <T> RetrieveEntity <T>(Clause clause, Sort sort) where T : TableEntity, new()
{
var sql = new StringBuilder();
var entity = new T();
sql.AppendLine(entity.SQLTableSelect);
List <DbParameter> parameters = null;
string txtClause = null;
if (clause != null)
{
clause.Export(this, out txtClause, out parameters);
}
if (!string.IsNullOrWhiteSpace(txtClause))
{
sql.AppendLine(" WHERE " + txtClause);
}
string txtSort = null;
if (sort != null)
{
sort.Export(out txtSort);
}
if (!string.IsNullOrWhiteSpace(txtSort))
{
sql.AppendLine(" ORDER BY " + txtSort);
}
var command = CreateCommand(sql.ToString(), parameters);
return(RetrieveEntity <T>(command, false));
}
public long CountInTable(string table, Clause clause = null)
{
ClearError();
if (string.IsNullOrWhiteSpace(table))
{
return(-1);
}
var sql = new StringBuilder();
sql.AppendLine(string.Format("SELECT COUNT(1) FROM {0}", table.Trim().ToUpper()));
List <DbParameter> parameters = null;
string txtClause = null;
if (clause != null)
{
clause.Export(this, out txtClause, out parameters);
}
if (!string.IsNullOrWhiteSpace(txtClause))
{
sql.AppendLine(" WHERE " + txtClause);
}
return(RetrieveValue <long>(CreateCommand(sql.ToString(), parameters)));
}
public List <T> Retrieve(int pageno)
{
var list = new List <T>();
if (pageno <= 0)
{
return(list);
}
if (Sort.Count <= 0)
{
return(list);
}
if (string.IsNullOrWhiteSpace(PageNOScript))
{
return(list);
}
string select = string.Empty;
using (var entity = TableEntity.CreateEntity <T>())
{
select = (entity != null) ? entity.SQLTableSelect : null;
}
if (string.IsNullOrWhiteSpace(select))
{
return(list);
}
string where = null;
List <DbParameter> parameters = null;
Clause.Export(Accessor, out where, out parameters);
if (!string.IsNullOrWhiteSpace(where))
{
select = string.Format("{0} WHERE {1}", select, where.ToString());
}
var sql = string.Format(SQL, PageNOScript, select, pageno);
string sort = null;
Sort.Export(out sort);
if (!string.IsNullOrWhiteSpace(sort))
{
sql = string.Format("{0} ORDER BY {1}", sql, sort);
}
list = Accessor.RetrieveEntity <T>(Accessor.CreateCommand(sql, parameters), false);
return(list);
}
