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ddlFindCb() - special FIND with Callback

Version 7.11

ddlFindCb() - special FIND with Callback

Prototype:

   void ddlFindCb(
      CONTROL *ctl,
      char *OptnStr,
      char *ArgList,
      char *DataArray[],
      int DataArrayItemCount,
      FindRtn FindCB,
      WtCastPtr UserWord);
 
   typedef int (STDCALL *FindRtn)(
      /* value 1 - continue FIND iteration; 0 - stop FIND iteration */
      WtCastPtr UserWord,
      long *FindRecArray,     /* array of 1-rel record numbers */
      int FindRecCount,       /* number of records found */
      int DataArrayIndex);

Permitted values in OptnStr: NA

Form of ArgList:
      <TableName> <RD-name> <key-name-1> [<key-name-2> ... [<key-name-N>]]

Where:

<TableName> is the name of the target table. <RD-name> is the name of an RD that describes each item in DataArray[] <key-name-N> is the name of the keyed field that is being queried

Description of Parameter *DataArray[]

char *DataArray[] is an array containing DataArrayItemCount pointers; although the pointers are of data type char*, each pointer is a pointer to a record image of arbitrary format.

Description:

ddlFindCb() is an optimized version of ddlFind(). In many respects, it is similar to ddlMatch(). In particular, ddlFindCb() performs an EQ query on each item of a vector, then returns the result via a callback; This methodology allows the user to implement his own MATCH-like function in an optimized fashion.

Notes:

Current restrictions as of TB API 8.0.160:        The one-key scenario is operable for index types:              . Non-RealTime - All modes              . Realtime - All modes              . Returns only the first record of each find        Is not operable for ATTACHed tables

ddlFindCb() Example

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