protected virtual SqlPlaceHolder CreateSqlPlaceHolder(ExternalValueExpression extValue)
{
var dataType = extValue.SourceExpression.Type;
var driver = this.DbModel.Driver;
var typeRegistry = driver.TypeRegistry;
var valueReader = BuildParameterValueReader(extValue.SourceExpression);
SqlPlaceHolder ph;
if (dataType.IsListOfDbPrimitive(out var elemType))
{
// list parameter
var elemTypeDef = typeRegistry.GetDbTypeDef(elemType);
Util.Check(elemTypeDef != null, "Failed to match DB type for CLR type {0}", elemType);
ph = new SqlListParamPlaceHolder(elemType, elemTypeDef, valueReader,
// ToLiteral
formatLiteral: list => driver.SqlDialect.ListToLiteral(list, elemTypeDef)
);
}
else
{
//regular linq parameter
var typeDef = typeRegistry.GetDbTypeDef(dataType);
Util.Check(typeDef != null, "Failed to find DB type for linq parameter of type {0}", dataType);
var dbConv = typeRegistry.GetDbValueConverter(typeDef.ColumnOutType, dataType);
Util.Check(dbConv != null, "Failed to find converter from type {0} to type {1}", dataType, typeDef.ColumnOutType);
ph = new SqlLinqParamPlaceHolder(dataType, valueReader, dbConv.PropertyToColumn, typeDef.ToLiteral);
}
this.PlaceHolders.Add(ph);
return(ph);
}
private string FormatLinqPlaceHolder(SqlLinqParamPlaceHolder ph, object arg)
{
var value = ph.ValueReader((object[])arg);
var dbValue = ph.ValueToDbValue(value) ?? DBNull.Value; //move it into converters? currently no-conv does not do this
var useLiteral = ShouldUseLiteral(dbValue);
if (useLiteral)
{
return(FormatAsLiteral(ph, dbValue));
}
else
{
var prm = _sqlDialect.AddDbParameter(_dbCommand, ph, dbValue);
var fmt = ph.FormatParameter;
return(fmt == null ? prm.ParameterName : fmt(prm));
}
}
