mco_cursor_store

Store the cursor for possible use by another transaction.

Prototype

 
    MCO_RET	mco_cursor_store(	/*IN*/ mco_trans_h t, /*IN*/ mco_cursor_h c);
 

Arguments

t

The mco_trans_h transaction handle returned by mco_trans_start()

c

A cursor handle returned from a cursor or index search function

Description

This function stores the cursor so that applications using the MVCC Transaction Manager can pass its handle between transacitons. For example, an application can search for an object, remember the found object’s position, and use it in the next transaction to avoid an additional lookup.

Return Codes

MCO_S_OK The cursor is valid
MCO_E_INVALID_HANDLE Cursor not opened

MCO_ERR_TRN

Transaction not open

MCO_E_CURSOR_CLOSED

Cursor has been closed

Example

 
    Application snippet:

     
    const char * dbname = "SimpleDb";
     
    int main(int argc, char* argv[])
    {
        mco_db_h db;
        MCO_RET rc;
        mco_device_t       dev;
        mco_db_params_t    db_params;
        mco_trans_h t;
        mco_cursor_t c;
        MCO_CURSOR_TYPE ctype;
         
        ...
        rc = mco_db_open_dev( dbname, simple_get_dictionary(), &dev, 1, &db_params );
        if ( MCO_S_OK != rc )
        {
            rc = mco_db_connect(  dbname, &db );
            ...
            rc = mco_trans_start(db, MCO_READ_ONLY, MCO_TRANS_FOREGROUND, &t);
            if ( MCO_S_OK == rc )
            {
                ...
                A_list_cursor( t, &c);
                ...
                rc = mco_cursor_store( t, &c );

                ...
            }
        }
        ...
    }
     
 

Files

Header file:
mco.h
Source file:
mcocsr.c
Library:
libmcolib.a