ArcGIS Pro 3.0 API Reference Guide
ArcGIS.Core.Data Namespace / QueryDef Class / PrefixClause Property

PrefixClause Property (QueryDef)
Gets or sets the prefix clause used by the query.
Syntax
public string PrefixClause {get; set;}
Remarks
A clause that will be inserted between the SELECT keyword and the SELECT COLUMN LIST (subfields). Most commonly used for clauses like DISTINCT or ALL, e.g., SELECT ArcGIS.Core.Data.QueryDef.PrefixClauseP:ArcGIS.Core.Data.QueryDef.PostfixClause.
Requirements

Target Platforms: Windows 11, Windows 10, Windows 8.1

ArcGIS Pro version: 2.0 or higher.
See Also