DF_FILE_FINDCACHE_HITS, DF_FILE_FINDCACHE_TIMEOUTS

The number of find cache hits for the table.

Level

Table

Supported by

The DataFlex SQL Drivers (SQL Server, DB2, and ODBC), revision 5 and higher.

Type

Integer, temporary

Access

Read / Write

Values

0..

Syntax

Use cli.pkg
Get_Attribute DF_FILE_FINDCACHE_HITS of {tableNumber} to {IntegerVariable}
Set_Attribute DF_FILE_FINDCACHE_HITS of {tableNumber} to {IntegerVariable}
Get_Attribute DF_FILE_FINDCACHE_TIMEOUTS of {tableNumber} to {IntegerVariable}
Set_Attribute DF_FILE_FINDCACHE_TIMEOUTS of {tableNumber} to {IntegerVariable}

Remarks

Two table-level attributes can be used to measure the effectiveness of the current find cache timeout setting. The attributes DF_FILE_FINDCACHE_HITS and DF_FILE_FINDCACHE_TIMEOUTS will return the number of cache hits (usage of cache) and timeouts (discarding the cache and getting data from the server), respectively. The find logic will increment the appropriate attribute when needed.

The attributes are kept in signed integer variables. Whenever incrementing the integer value of one of the attributes causes the value to become negative, both variables will be set to 0 (zero). It is possible to set the attributes to 0 (zero, the only allowed value). Setting one of the attributes will automatically cause the other attribute to be set to 0 (zero).

Example

The sample procedure below shows the hits and timeouts for every open table.

Procedure ShowFindCacheEffectiveness
    Handle hTable
    Integer iHits
    Integer iTimeouts
    String sName

    Showln "Table, hits, Timeouts"
    Move 0 To hTable
    Get_Attribute DF_FILE_NEXT_OPENED Of hTable To hTable

    While (hTable <> 0)
        Get_Attribute DF_FILE_FINDCACHE_HITS Of hTable To iHits
        Get_Attribute DF_FILE_FINDCACHE_TIMEOUTS Of hTable To iTimeouts
        Get_Attribute DF_FILE_LOGICAL_NAME Of hTable To sName
        Showln sName ", " iHits ", " iTimeouts
        Get_Attribute DF_FILE_NEXT_OPENED Of hTable To hTable
    End
End_Procedure // ShowFindCacheEffectiveness