JoinType Property (JoinDescription)
Gets or sets a value indicating whether the join is an inner join or a left outer join. The default value is
JoinType.InnerJoin.
Joining a file geodatabase feature class to an Oracle database query layer feature class with a virtual relationship class
public async Task JoiningFileGeodatabaseFeatureClassToOracleQueryLayer()
{
await ArcGIS.Desktop.Framework.Threading.Tasks.QueuedTask.Run(() =>
{
using (Geodatabase geodatabase = new Geodatabase(new FileGeodatabaseConnectionPath(new Uri("C:\\Data\\LocalGovernment.gdb"))))
using (Database database = new Database(new DatabaseConnectionProperties(EnterpriseDatabaseType.Oracle)
{
AuthenticationMode = AuthenticationMode.DBMS,
Instance = "instance",
User = "user",
Password = "password",
Database = "database"
}))
using (FeatureClass leftFeatureClass = geodatabase.OpenDataset<FeatureClass>("Hospital"))
using (Table rightTable = database.OpenTable(database.GetQueryDescription("FacilitySite")))
{
Field originPrimaryKey = leftFeatureClass.GetDefinition().GetFields().FirstOrDefault(field => field.Name.Equals("facilityId"));
Field destinationForeignKey = rightTable.GetDefinition().GetFields().FirstOrDefault(field => field.Name.Equals("hospitalID"));
VirtualRelationshipClassDescription description = new VirtualRelationshipClassDescription(
originPrimaryKey, destinationForeignKey, RelationshipCardinality.OneToOne);
using (RelationshipClass relationshipClass = leftFeatureClass.RelateTo(rightTable, description))
{
JoinDescription joinDescription = new JoinDescription(relationshipClass)
{
JoinDirection = JoinDirection.Forward,
JoinType = JoinType.LeftOuterJoin
};
Join join = new Join(joinDescription);
using (Table joinedTable = join.GetJoinedTable())
{
// Perform operation on joined table.
}
}
}
});
}
Joining two tables from different geodatabases
public async Task JoinTablesFromDifferentGeodatabases()
{
await ArcGIS.Desktop.Framework.Threading.Tasks.QueuedTask.Run(() =>
{
using (Geodatabase sourceGeodatabase = new Geodatabase(new FileGeodatabaseConnectionPath(new Uri("Path \\ to \\Geodatabase \\ one"))))
using (Geodatabase destinationGeodatabase = new Geodatabase(new FileGeodatabaseConnectionPath(new Uri("Path \\ to \\Geodatabase \\ two"))))
using (Table sourceTable = sourceGeodatabase.OpenDataset<Table>("State"))
using (Table destinationTable = destinationGeodatabase.OpenDataset<Table>("Cities"))
{
Field primaryKeyField = sourceTable.GetDefinition().GetFields().FirstOrDefault(field => field.Name.Equals("State.State_Abbreviation"));
Field foreignKeyField = destinationTable.GetDefinition().GetFields().FirstOrDefault(field => field.Name.Equals("Cities.State"));
VirtualRelationshipClassDescription virtualRelationshipClassDescription = new VirtualRelationshipClassDescription(primaryKeyField, foreignKeyField, RelationshipCardinality.OneToMany);
using (RelationshipClass relationshipClass = sourceTable.RelateTo(destinationTable, virtualRelationshipClassDescription))
{
JoinDescription joinDescription = new JoinDescription(relationshipClass)
{
JoinDirection = JoinDirection.Forward,
JoinType = JoinType.InnerJoin,
TargetFields = sourceTable.GetDefinition().GetFields()
};
using (Join join = new Join(joinDescription))
{
Table joinedTable = join.GetJoinedTable();
//Process the joined table. For example ..
using (RowCursor cursor = joinedTable.Search())
{
while (cursor.MoveNext())
{
using (Row row = cursor.Current)
{
// Use Row
}
}
}
}
}
}
});
}
Target Platforms: Windows 11, Windows 10
ArcGIS Pro version: 3 or higher.