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C++ Dbt::set_doff方法代码示例

本文整理汇总了C++中Dbt::set_doff方法的典型用法代码示例。如果您正苦于以下问题:C++ Dbt::set_doff方法的具体用法?C++ Dbt::set_doff怎么用?C++ Dbt::set_doff使用的例子?那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在Dbt的用法示例。


在下文中一共展示了Dbt::set_doff方法的2个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的C++代码示例。

示例1: fprintf

/**
 * Cursor must be closed before the transaction is aborted/commited.
 * http://download.oracle.com/docs/cd/E17076_02/html/programmer_reference/transapp_cursor.html
 */
Bdb::ResponseCode Bdb::
update(const std::string& key, const std::string& value)
{
    if (!inited_) {
        fprintf(stderr, "insert called on uninitialized database");
        return Error;
    }
    DbTxn* txn = NULL;
    Dbc* cursor = NULL;

    Dbt dbkey, dbdata;
    dbkey.set_data(const_cast<char*>(key.c_str()));
    dbkey.set_size(key.size());
    dbdata.set_data(const_cast<char*>(value.c_str()));
    dbdata.set_size(value.size());

    Dbt currentData;
    currentData.set_data(NULL);
    currentData.set_ulen(0);
    currentData.set_dlen(0);
    currentData.set_doff(0);
    currentData.set_flags(DB_DBT_USERMEM | DB_DBT_PARTIAL);

    int rc = 0;
    for (uint32_t idx = 0; idx < numRetries_; idx++) {
        env_->txn_begin(NULL, &txn, 0);
        (*db_).cursor(txn, &cursor, DB_READ_COMMITTED);

        // move the cursor to the record.
        rc = cursor->get(&dbkey, &currentData, DB_SET | DB_RMW);
        if (rc != 0) {
            cursor->close();
            txn->abort();
            if (rc == DB_NOTFOUND) {
                return KeyNotFound;
            } else if (rc != DB_LOCK_DEADLOCK) {
                fprintf(stderr, "Db::get() returned: %s", db_strerror(rc));
                return Error;
            }
            continue;
        }

        // update the record.
        rc = cursor->put(NULL, &dbdata, DB_CURRENT);
        cursor->close();
        if (rc == 0) {
            txn->commit(DB_TXN_SYNC);
            return Success;
        } else {
            txn->abort();
            if (rc != DB_LOCK_DEADLOCK) {
                fprintf(stderr, "Db::put() returned: %s", db_strerror(rc));
                return Error;
            }
        }
    }
    fprintf(stderr, "update failed %d times", numRetries_);
    return Error;
}
开发者ID:BigR-Lab,项目名称:mapkeeper,代码行数:63,代码来源:Bdb.cpp

示例2: del

void Database::del(const RecordID& id)
{
	Dbt key(id.data(), id.size());
	// fetch children
	std::vector<RecordID> childrenIds;
	Dbc* pCursor = nullptr;
	dbParentId_.cursor(NULL, &pCursor, 0);
	assert(pCursor);
    
    BOOST_SCOPE_EXIT(&pCursor) 
    {
        if(pCursor) pCursor->close();
    } BOOST_SCOPE_EXIT_END
	
	Dbt keyChild;
	Dbt record;
	record.set_flags(DB_DBT_PARTIAL);
	record.set_doff(0);
	record.set_dlen(0);
	
	int res = pCursor->pget(&key, &keyChild, &record, DB_SET);
	
	while (res == 0)
	{
		childrenIds.push_back(RecordID(keyChild));
		res = pCursor->pget(&key, &keyChild, &record, DB_NEXT_DUP);
	}
	
	if (res != DB_NOTFOUND)
	{
		throw DbException("Failed to obtain children ids", res);
	}
	
	pCursor->close();
    pCursor = nullptr;
	
	// delete children
	for (const RecordID& childId : childrenIds)
	{
		del(childId);
	}
	
	// delete the record itself
	const int err = dbMain_.del(nullptr, &key, /*flags*/0);
	
	if (err && err != DB_NOTFOUND)
	{
		std::ostringstream ss;
		ss << "Failed to delete record id='" << id << '\'';
		throw DbException(ss.str().c_str(), err);
	}
}
开发者ID:sgomin,项目名称:ddb_medialib,代码行数:52,代码来源:database.cpp


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