tayafluid.blogg.se - Esri make query table tool 10.5

Spatial reference-This is the coordinate system and other related spatial properties for the layer.Geometry type-This determines whether the layer is a point, multipoint, line, or polygon.

Dimensionality-This determines whether a layer's coordinates will include m-values to store route data and z-values to store 3D data.

Unique identifier field-This is one or many fields used by ArcGIS to uniquely identify the layer.

The properties of a query layer are the following: During validation, ArcGIS attempts to determine the properties of the query layer based on the first row returned in the table. Once the query is created, it must be validated. For more information on building SQL queries, see Building a query expression. In ArcMap, this would display all the United States. This would result in a query layer containing all rows from the US_States table. A common example would be as follows: SELECT * FROM _States. SQL syntax specific to the database should be used when building a query layer.

You can also type specific queries or cut and paste a query from an external application into the Query text box. Likewise, you can add specific columns in a table to the query by double-clicking them or dragging them from the Columns window into the Query text box. When building a query, a whole table can be added to the Query text box by either double-clicking it or dragging it from the List of Tables window into the Query text box. You specify an SQL query in the Query text box.

To learn more about the data types that ArcGIS supports, see Data types supported in ArcGIS. When you specify a query, all columns that have an unknown data type must either be excluded or changed in the query to a different data type that ArcGIS supports. If the attribute column type is Unknown, this indicates that ArcGIS does not support that data type. However, some less common database types are not supported. ArcGIS can work with most common database types. Each column in a database has a specific data type.