DateTimePartExpression

The DateTimePartExpression is part of the Dynamic Where feature; it represents a call to the SQL function that extracts a part of given date like year, month etc.

Date parts that can be extracted:

Year Month Week Day Hour Minute Second

Implementations

Example

Target SQL where clause:

WHERE DATEPART(order_date, YEAR) = 2020

 

WhereExpression whereExpression = new BinaryExpression(
                  new DateTimePartExpression(
                    new FieldExpression("ORDERS", "order_date"),
                    DatePart.Year),
                  new ConstantExpression(2020, DataType.Integer),
                  BinaryOperator.Equal);

 

let whereExpression = BinaryExpression(
            DateTimePartExpression(
              FieldExpression("ORDERS", "order_date"),
              DatePart.Year),
            ConstantExpression(2020, DataType.Integer),
            BinaryOperator.Equal)

 

WhereExpression where = new BinaryExpression(
                  new DateTimePartExpression(
                    new FieldExpression("ORDERS", "order_date"),
                    DatePart.Year),
                  new ConstantExpression(2020, DataType.Integer),
                  BinaryOperator.Equal);

 

let whereExpression = BinaryExpression(
            DateTimePartExpression(
              FieldExpression("ORDERS", "order_date"),
              DatePart.Year),
            ConstantExpression(2020, DataType.Integer),
            BinaryOperator.Equal)

 

with ClientDataModule.tbl_ORDERS, DynamicWhere do begin
  Expression := NewBinaryExpression(
          NewDateTimePart(
            NewField(LogicalName, 'order_date'),
            ddpYear),
          NewConstant(2020, datInteger),
          dboEqual);
end;

 

myTable.dynamicWhere = new RemObjects.DataAbstract.DynamicWhere(
        new RemObjects.DataAbstract.DateTimePartExpression(
          new RemObjects.DataAbstract.FieldExpression("order_date"),
          "Year"),
        new RemObjects.DataAbstract.ConstantExpression("Integer", 2020),
        "Equal");

Generated XML/JSON

<?xml version="1.0"?>
<query xmlns="http://www.remobjects.com/schemas/dataabstract/queries/5.0" version="5.0">
    <where>
        <binaryoperation operator="Equal">
            <datetimepart part="Year">
                <field tablename="ORDERS">order_date</field>
            </datetimepart>
            <constant type="Integer" null="0">2020</constant>
        </binaryoperation>
    </where>
</query>

{
  "type": "query.where",
  "expression": {
    "type": "binaryoperation",
    "left": {
      "type": "datetimepart",
      "part": "Year",
      "expression": {
        "type": "field",
        "field": "order_date",
        "table": "ORDERS"
      }
    },
    "operator": "Equal",
    "right": {
      "type": "constant",
      "datatype": "Integer",
      "value": "2020"
    }
  }
}