/// Visits a LINQ expression using a new expression visitor and returns a part of the PostgreSQL query it represents.
private string GetNestedPsqlExpression(Expression linqExpression)
{
var visitor = new PsqlGeneratingExpressionVisitor(_queryModelVisitor);
visitor.Visit(linqExpression);
return(visitor.GetPsqlExpression());
}
public static string GetPsqlExpression(Expression linqExpression, PsqlGeneratingQueryModelVisitor queryModelVisitor, ExpressionVisitorOptions options)
{
var visitor = new PsqlGeneratingExpressionVisitor(queryModelVisitor, options);
visitor.Visit(linqExpression);
return(visitor.GetPsqlExpression());
}
public override void VisitWhereClause(WhereClause whereClause, QueryModel queryModel, int index)
{
var wherePredicateType = whereClause.Predicate.GetType();
if (whereClause.Predicate is SubQueryExpression subQuery)
{
var t = subQuery.QueryModel.BodyClauses;
if (subQuery.QueryModel.SelectClause.Selector is QuerySourceReferenceExpression _sExpression)
{
var z = _sExpression.ReferencedQuerySource.ToString();
var z1 = z.Split(' ').LastOrDefault();
var z2 = z1?.Split(".".ToCharArray(), 2)[1];
_queryParts.AddWherePart(z2);
foreach (var queryModelBodyClause in subQuery.QueryModel.BodyClauses)
{
if (queryModelBodyClause is WhereClause where)
{
var opts = new ExpressionVisitorOptions();
opts.TableName = z2;
var expr = PsqlGeneratingExpressionVisitor.GetPsqlExpression(where.Predicate, this, opts); GetPsqlExpression(where.Predicate);
_queryParts.AddWherePart(expr);
}
//var props = queryModelBodyClause.ToString().Split('.').Skip(1).ToList();
}
}
_queryParts.AddWherePart(GetPsqlExpression(whereClause.Predicate));
}
else
{
_queryParts.AddWherePart(GetPsqlExpression(whereClause.Predicate));
}
//_queryParts.AddWherePart(GetPsqlExpression(whereClause.Predicate));
base.VisitWhereClause(whereClause, queryModel, index);
}
/// Creates an instance of the PsqlGeneratingExpressionVisitor based on this PsqlGeneratingQueryModelVisitor instance to visit the LINQ expression provided as an argument and to generate a corresponding part of the PostgreSQL query.
private string GetPsqlExpression(Expression expression)
{
return(PsqlGeneratingExpressionVisitor.GetPsqlExpression(expression, this));
}
/// Visits the QueryModel nested in a SubQueryExpression using this PsqlGeneratingQueryModelVisitor.
private void VisitSubQueryExpression(Expression expression)
{
PsqlGeneratingExpressionVisitor.GetPsqlExpression(expression, this);
}
