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SumIndexFields Property

  • บทความ

Version: Available or changed with runtime version 1.0.

Specify which fields should be the "aggregation fields" in a SumIndexField Technology (SIFT) index, if applicable.

Applies to

  • Table key

Syntax

key(<key name>;<comma-separated list of lookup fields>) { 
            SumIndexFields=<comma-separated list of aggregation fields>; 
        }

Example

table 50100 Student
{
    DataClassification = CustomerContent;
    fields
    {
        field(1; Code; Text[50])
        {
            DataClassification = EndUserPseudonymousIdentifiers;
        }
        field(2; FirstNames; Text[100])
        {
            DataClassification = EndUserIdentifiableInformation;
        }
        field(3; ECTSPoints; Integer)
        {
            DataClassification = CustomerContent;
        }
        field(4; NumberOfCourses; Integer)
        {
            DataClassification = CustomerContent;
        }
    }
    // this defines a SIFT index on Code, FirstNames with aggregations fields for count, SUM(ECTSPoints), and SUM(NumberOfCourses)
    // Because MaintainSqlIndex is set to false, no non-clustered index is created on (Code,FirstNames)
    // 
    keys
    {
        key(SIFTKeyOnCode;Code,FirstNames) { 
            SumIndexFields=ECTSPoints,NumberOfCourses; 
            MaintainSqlIndex = false;            
        }
    }
}

Remarks

You can select up to 20 SumIndexFields for each key.

The fields must be of a numeric datatype (Decimal, Integer, BigInteger, or Duration).

Changing existing keys may affect the behavior of the application since other parts of your application may depend on the existence of certain keys.

Properties
MaintainSIFTIndex Property
MaintainSQLIndex Property
AL Data Types