嗨,当查询在过滤后返回 0 个结果时,我收到此错误。
我该如何解决这个问题?
这是我的代码。
> router.post('/report/', jsonParser, function (req, res) {
var data = req.body,
filteredID = data.filteredID,
startRow = data.startRow,
numRows = data.numRows,
sortCol = data.sortCol,
sortDir = data.sortDir;
var countQuery = 'SELECT COUNT(*) ' +
'FROM this_view ' ;+
var query = 'SELECT * +
'FROM this_view ' ;
var seg,
orderBy,
offset;
if(filteredID !== null && filteredID !== ""){
seg = ' WHERE "ID" LIKE \'%'+ filteredID + '%\'';
query += seg;
countQuery += seg;
}
orderBy = ' ORDER BY UPPER(' + sortCol + ') ' + sortDir;
offset = ' OFFSET ' + startRow + ' ROWS FETCH NEXT ' + numRows + ' ROWS ONLY';
query += orderBy;
query += offset;
logger.info("Begin: " + (new Date().toString()));
async.parallel({
rows: function (callback) {
pool.getConnection(function (err, connection) {
logger.info("Begin Connection: " + (new Date().toString()));
if (err) {
logger.error(err.message);
return;
}
logger.info("Begin execute: " + (new Date().toString()));
connection.execute(
query,
[],
{
resultSet: true,
prefetchRows: 1000
},
function (err, result) {
logger.info("End execute: " + (new Date().toString()));
if (err) {
logger.error(err.message);
callback("Something broke in the first thing");
doRelease(connection);
return;
}
function fetchRowsFromRS(connection, resultSet, numRows) {
result.resultSet.getRows(
numRows, // get this many rows
function (err, rows) {
if (err) {
logger.error(err);
doClose(connection, resultSet); // always close the result set
} else if (rows.length >= 0) {
var procJson = [];
/**
* For each row in the result, pushes a new object to the rows array
* In each new object, the key is assigned and the result row value set
*/
for (var i = 0; i < rows.length; i++) {
procJson.push({});
for (var j = 0; j < resultSet.metaData.length; j++) {
procJson[i][resultSet.metaData[j].name.toLowerCase()] = rows[i][j];
}
}
//TODO: Add null handling
logger.info("Send JSON: " + (new Date().toString()));
callback(null, procJson);
logger.info("JSON Sent: " + (new Date().toString()));
if (rows.length === numRows) // might be more rows
fetchRowsFromRS(connection, resultSet, numRows);
else
doClose(connection, resultSet); // always close the result set
} else { // no rows
doClose(connection, resultSet); // always close the result set
}
});
}
fetchRowsFromRS(connection, result.resultSet, numRows)
});
});
},
totalRows: function (callback) {
pool.getConnection(function (err, connection) {
logger.info("Begin Connection: " + (new Date().toString()));
if (err) {
logger.error(err.message);
return;
}
logger.info("Begin execute: " + (new Date().toString()));
connection.execute(
countQuery,
function (err, result) {
logger.info("End execute: " + (new Date().toString()));
if (err) {
logger.error(err.message);
callback("Something broke");
doRelease(connection);
return;
}
logger.info("Send JSON: " + (new Date().toString()));
console.log(result.rows);
callback(null, result.rows[0][0]);
logger.info("JSON Sent: " + (new Date().toString()));
doRelease(connection);
});
});
}
}, function(err, result){
if(err){
logger.error(err);
}
res.send(result);
});
});
如果 rows.length >= 0,我会收到此错误。如果我只使用“rows.length > 0”并且如果查询后出现 0 个结果,则它会失败。
是否有任何其他替代 async.parallel 可以解决此问题?请帮忙。