Expression Fields in Advanced views

AdministradorData_Gis — Tue, 07 Dec 2021 02:09:13 GMT

Hi everyone,

I am trying to create an advanced view according to this documentation Advanced views , this is my code:

{ "layers": [ { "name": "VistaAvanzada", "description": "AttributeJoin", "adminLayerInfo": { "viewLayerDefinition": { "table": { "name": "target", "sourceServiceName": "TestJoinExpression_Tabla1", "sourceLayerId": 0, "sourceLayerFields": [ { "name": "key1", "alias": "key1", "source": "key1" }, { "name": "date1", "alias": "date1", "source": "date1" } ], "relatedTables": [ { "name": "joined", "sourceServiceName": "TestJoinExpression_Tabla2", "sourceLayerId": 0, "sourceLayerFields": [ { "name": "key1related", "alias": "key1related", "source": "key1related" }, { "name": "name", "alias": "name", "source": "name" }, { "name": "relatedExpression", "alias": "SumNumsTest", "expression": "Num1 + Num2", "type": "esriFieldTypeInteger" } ], "type": "INNER", "parentKeyFields": [ "key1", "key2" ], "keyFields": [ "key1related", "key2related" ] } ] } } } } ] }

For this test, I have created the fields Num1 and Num2, in both tables, because I am not sure how the expression works, however the expression field "relatedExpression" is not created, I can see the fields I declared, coming from both tables. That is, the view works for me as a union of tables, but I cannot create the additional field that corresponds to the expression.

I appreciate the help

Re: Expression Fields in Advanced views

ponlawat_w — Wed, 05 Apr 2023 02:21:13 GMT

It has been 2 years so I am not sure if you already have it fixed yet, but I got it solved by adding "source" property to field object referring to at least one field whose value being used in the expression, then the field displayed normally.

Example:

[ { // calculate value on single field "name": "testField", "type": "esriFieldTypeInteger", "alias": "testField", "expression": "myNumberField1 * 2", "source": "myNumberField1" }, { // calculate value on multiple fields, only one field needed in source "name": "testField2", "type": "esriFieldTypeInteger", "alias": "testField2", "expression": "myNumberField1 + myNumberField2", "source": "myNumberField1" }, { // calculate static value for all records, source field must be there even it is irrelevant "name": "testField3", "type": "esriFieldTypeString", "alias": "testField3", "expression": "'Hello World!'", "source": "OBJECTID" }, { // example of advanced SQL to get hour part from date field "name": "hourOfDay", "type": "esriFieldTypeInteger", "alias": "hourOfDay", "expression": "DATEPART(HOUR, myDateField)", "source": "myDateField" } ]

Hope this helps.

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Expression Fields in Advanced views

Re: Expression Fields in Advanced views