/// <summary>
/// Deletes rows from a table using a variable list of and-connected where
/// conditions. Fields identified using the 'parameters' collection need not
/// be part of the primary key.
/// </summary>
public static commandprimitive delete_wildcard(Iddl db, string targettable, deletecommandparameters parameters)
{
expressionlist expressions = new expressionlist();
/* build the where clause */
bool bneedand = false;
foreach (deletecommandparameter parm in parameters)
{
if (bneedand)
{
expressions.Add(where_and);
}
if (parm.size.HasValue)
{
expressions.Add(where_fld_eq_p(parm.fieldname, parm.paramname, parm.paramtype, parm.size.Value));
}
else
{
expressions.Add(where_fld_eq_p(parm.fieldname, parm.paramname, parm.paramtype));
}
bneedand = true;
}
if (expressions.Count <= 0)
{
throw new ArgumentOutOfRangeException("parameters", "Cannot execute a delete_wildcard statement without specifying any restrictions.");
}
/* compose the final statement */
deletestatement del = new deletestatement(
targettable,
new whereclause(expressions)
);
return(new commandadhoc(db, del));
}
protected override bool CompileDelete()
{
deletestatement st = stmt as deletestatement;
RegisterDeleteRowsourceQualifierAliases(st);
/* 1. get the header part */
s = new StringBuilder();
string tableliteral;
if (!GetSubquery(st.TargetTable, true, out tableliteral))
{
throw new InvalidOperationException();
}
/* [dlatikay 20110323] syntax is "delete x from table x where" */
string alias_if_needed = String.Empty;
if (!String.IsNullOrWhiteSpace(st.TargetTable.Alias))
{
alias_if_needed = st.TargetTable.Alias + " ";
}
/* render the statement */
s.AppendLine(sindent + String.Format("DELETE {0}FROM {1}", alias_if_needed, tableliteral.Trim()));
/* 2. render the where clause */
if (st.Where != null)
{
AppendWhereClause(s, st.Where);
}
return(true);
}
protected override bool CompileDelete()
{
deletestatement st = stmt as deletestatement;
/* 1. get the header part */
s = new StringBuilder();
string tableliteral;
if (!GetSubquery(st.TargetTable, true, out tableliteral))
{
throw new InvalidOperationException();
}
s.AppendLine(sindent + String.Format("DELETE * FROM {0}", tableliteral.Trim()));
/* 2. render the where clause */
if (st.Where != null)
{
AppendWhereClause(s, st.Where);
}
return(true);
}
