/// <summary>
/// Visit a parse tree produced by <see cref="SqlParser.select_core"/>.
/// <para>
/// The default implementation returns the result of calling <see cref="AbstractParseTreeVisitor{Result}.VisitChildren(IRuleNode)"/>
/// on <paramref name="context"/>.
/// </para>
/// </summary>
/// <param name="context">The parse tree.</param>
/// <return>The visitor result.</return>
public virtual Result VisitSelect_core([NotNull] SqlParser.Select_coreContext context)
{
return(VisitChildren(context));
}
public override object VisitSelect_core([NotNull] SqlParser.Select_coreContext context)
{
SelectStatement select = null;
select = new SelectStatement();
if (context.table_or_subquery() != null)
{
if (context.table_or_subquery().Length > 1)
{
select.Table = (TableName)VisitTable_or_subquery(context.table_or_subquery(0));
select.IsJoin = true;
select.JoinTables = new List <JoinTable>();
for (int i = 1; i < context.table_or_subquery().Length; i++)
{
select.JoinTables.Add((new JoinTable()
{
JoinType = JoinType.Unknown,
Table = (TableName)VisitTable_or_subquery(context.table_or_subquery(i))
}));
}
}
else if (context.table_or_subquery().Length == 1)
{
select.Table = (TableName)VisitTable_or_subquery(context.table_or_subquery(0));
}
}
if (context.join_clause() != null)
{
select.IsJoin = true;
select.Table = (TableName)VisitTable_or_subquery(context.join_clause().table_or_subquery());
var noAlias = false;;
if (select.Table.Alias.ToUpper() == "INNER" || select.Table.Alias.ToUpper() == "CROSS")
{
noAlias = true;
}
select.JoinTables = new List <JoinTable>();
foreach (var item in context.join_clause().join_right())
{
var joinTable = (JoinTable)VisitJoin_right(item);
if (noAlias)
{
joinTable.JoinType = select.Table.Alias.ToUpper() == "INNER" ? JoinType.Inner : JoinType.Cross;
select.Table.Alias = "";
}
select.JoinTables.Add(joinTable);
}
}
if (context.result_column() != null)
{
select.Columns = new List <ColumnExpression>();
foreach (var item in context.result_column())
{
select.Columns.Add((ColumnExpression)VisitResult_column(item));
}
}
if (context.where_clause() != null)
{
select.Where = (IExpression)VisitWhere_clause(context.where_clause());
if (select.Where is LiteralValueExpression)
{
throw new SQLParseException($"Incorrect syntax near '{context.where_clause().GetChild(0)}'");
}
}
if (context.groupby_clause() != null)
{
select.Groupby = (GroupbyClause)VisitGroupby_clause(context.groupby_clause());
}
return(select);
}
