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是否可以增加其他语言的性能对比。比如js和golang

请问可以增加rust js等其他语言的性能对比。

基于Cmake,发布dolphindb C++ lib，可以完全跨平台。并发布到vcpkg port。发布，使用都非常方便。

请问下如果宽表情况下存储因子，新增股票ID时怎么办呢，能够横向增加吗？

在按照docker部署教程步骤，到执行docker-compose up -d 遇到以下问题：

ERROR: Version in "./docker-compose.yml" is unsupported. You might be seeing this error because you're using the wrong Compose file version. Either specify a version of "2" (or "2.0") and place your service definitions under the services key, or omit the version key and place your service definitions at the root of the file to use version 1.
For more on the Compose file format versions, see https://docs.docker.com/compose/compose-file/

在同時 insert db 時，出現這個 error

RuntimeError: in run: filepath 'xxx/xxx/20051013' has been owned by transaction 4717

是否可以同時 insert ?

n=1000000
ID=rand(10, n)
x=rand(1.0, n)
t=table(ID, x)
db=database("dfs://rangedb", RANGE,  0 5 10)
pt=db.createPartitionedTable(t, `pt, `ID)
pt.append!(t);

另外，如果不能同時 insert，有沒有 function，可以判斷，DB 是否被 lock 住

請問未來 Community 版本有計畫支援 8GB RAM 嗎?

目前我跟我身邊的朋友使用起來，都覺得 4GB 不太夠用，謝謝

請問要怎麼解決這個問題?
感謝

节点启动后立即退出

image: dolphindb/dolphindb:v2.00.7 

root@ubuntu:/mnt/test/dolphinDB/DolphinDB-Docker-Compose# docker-compose up
[+] Running 5/5
 ⠿ Network dolphindb-docker-compose_dbnet  Created                                                                                                                                   0.1s
 ⠿ Container ddbagent1                     Created                                                                                                                                   0.5s
 ⠿ Container ddbcontroller                 Created                                                                                                                                   0.5s
 ⠿ Container ddbagent2                     Created                                                                                                                                   0.5s
 ⠿ Container ddbagent3                     Created                                                                                                                                   0.5s
Attaching to ddbagent1, ddbagent2, ddbagent3, ddbcontroller
ddbagent3 exited with code 255
ddbagent1 exited with code 255
ddbcontroller exited with code 255
ddbagent2 exited with code 255
root@ubuntu:/mnt/test/dolphinDB/DolphinDB-Docker-Compose#

如何把，日資料，轉換成週K、月K?

关闭防火墙后，按照单机集群教程能搭建起来社区集群，
数据节点也能正常启用，
但是启用防火墙后就连接不上了数据节点，也无法启用。

端口8910/8920/8921/8922/8848有开放的。

[xxx@localhost DolphinDB]$ firewall-cmd --zone=public --list-ports
3389/tcp 8910/tcp 8920/tcp 8921/tcp 8922/tcp 8848/tcp

是不是还漏了哪些端口？

請問 PartitionedTable ( dfs ) 支援 unique key 嗎?

或是 dolphindb 有其他方法，避免重複的 data insert

in-memory table with primary key，
memory table 可以透過設定 primary key 避免重複 data

不知 dfs 的 table 是否有類似功能?

謝謝

组合 (COMPO) 分区 实测在 1.10.11 版本中可以使用 HASH 分区作为分区列，文档中遗漏了这一类型。

浅谈 4 点，可以主要看 1-3。

1. 比如关于数据形式的介绍里，将 createPartitionedTable 称为“分布式表” 就根本错误，因为分区表的页面显示，可以创建在本次磁盘、分布式系统或内存中。

2. 维度表和分布式表不是平行关系，是包含关系。下图中，“维度表”和“分布式表”被如此提及，让人感觉维度表既不是内存表，也不是分布式表。而实际从维度表的介绍中，可以发现维度表只能是分布式表。

3. 关键定义混乱或冗余。比如冗余：排序列/索引列对于分区表其实很重要，但是如下介绍中 定义了一个 sort key entry，但是后文再也没有使用过这个概念，都是在说 sort key 组合值/数，那定义这个entry做什么呢？；比如混乱：这里涉及到两个关键概念：sort key， 排序列，两者的关系没有明确的说明，需要读者去推导才能知道“sort key 是不包含自动添加的时间戳列的排序列”（姑且认为是这样）。而且sort key从上下文看译名居然是“索引列”，恰恰直译的“排序列”又是另一个概念，为什么要使用如此容易混淆的术语呢？

4. 对于可能相同的内容复制粘贴，导致概念混淆。比如维度表和分区表都要有 sortColumn，但是维度表没有分区啊，结果如下维度表介绍中有提到了分区概念。

1. typescript/js api sdk
2. websocket support

不支持macos安装吗

如題，我用的是社群版本，經常發生
src/central_freelist.cc:330] tcmalloc: allocation failed 8192
想問是我記憶體問題嗎?

我用的版本是，DolphinDB_Linux64_V1.20.5

由于存储数据时发生问题，服务崩溃。随后，我在硬盘上将某一个db的目录全部删除，然后重启服务，现在日志里面一直提示：
:The data node [local11089] isn't ready for service [getClusterDFSDatabases] yet.

这导致我无法访问数据库中其他db中的数据。请问这种情况下应该如何处理？

dolphin db 版本 v2.00.9.2

I tried the following lines in the dolphindb command line after running ./dolphindb. However, it reports the error "Can't find module [ta]". Seems that the ta module is not included in zip file. Is the ta module opensourced?

根据官网教程案例，执行该脚本中的writeInSnapshotByDay()方法生成模拟数据时，内存溢出。
我本机内存是64G的，是DDB哪里限制了内存吗？

完整报错信息：
15:21:32.060 local8848
writeInSnapshotByDay(5)
writeInSnapshotByDay(5) => writeInSnapshotByDay: genSnapshotOrigin(n) => genSnapshotOrigin: resTable = select *,rand(100, size(tmpTable)) as PreClosePx,rand(100, size(tmpTable)) as OpenPx,rand(100, size(tmpTable)) as HighPx,rand(100, size(tmpTable)) as LowPx,rand(100, size(tmpTable)) as LastPx,rand(100, size(tmpTable)) as TotalVolumeTrade,rand(100, size(tmpTable)) as TotalValueTrade,rand(["a","b","c"], size(tmpTable)) as InstrumentStatus,rand(100, size(tmpTable)) as BidPrice0,rand(100, size(tmpTable)) as BidPrice1,rand(100, size(tmpTable)) as BidPrice2,rand(100, size(tmpTable)) as BidPrice3,rand(100, size(tmpTable)) as BidPrice4,rand(100, size(tmpTable)) as BidPrice5,rand(100, size(tmpTable)) as BidPrice6,rand(100, size(tmpTable)) as BidPrice7,rand(100, size(tmpTable)) as BidPrice8,rand(100, size(tmpTable)) as BidPrice9,rand(100, size(tmpTable)) as BidOrderQty0,rand(100, size(tmpTable)) as BidOrderQty1,rand(100, size(tmpTable)) as BidOrderQty2,rand(100, size(tmpTable)) as BidOrderQty3,rand(100, size(tmpTable)) as BidOrderQty4,rand(100, size(tmpTable)) as BidOrderQty5,rand(100, size(tmpTable)) as BidOrderQty6,rand(100, size(tmpTable)) as BidOrderQty7,rand(100, size(tmpTable)) as BidOrderQty8,rand(100, size(tmpTable)) as BidOrderQty9,rand(100, size(tmpTable)) as BidOrders0,rand(100, size(tmpTable)) as BidOrders1,rand(100, size(tmpTable)) as BidOrders2,rand(100, size(tmpTable)) as BidOrders3,rand(100, size(tmpTable)) as BidOrders4,rand(100, size(tmpTable)) as BidOrders5,rand(100, size(tmpTable)) as BidOrders6,rand(100, size(tmpTable)) as BidOrders7,rand(100, size(tmpTable)) as BidOrders8,rand(100, size(tmpTable)) as BidOrders9,rand(100, size(tmpTable)) as OfferPrice0,rand(100, size(tmpTable)) as OfferPrice1,rand(100, size(tmpTable)) as OfferPrice2,rand(100, size(tmpTable)) as OfferPrice3,rand(100, size(tmpTable)) as OfferPrice4,rand(100, size(tmpTable)) as OfferPrice5,rand(100, size(tmpTable)) as OfferPrice6,rand(100, size(tmpTable)) as OfferPrice7,rand(100, size(tmpTable)) as OfferPrice8,rand(100, size(tmpTable)) as OfferPrice9,rand(100, size(tmpTable)) as OfferOrderQty0,rand(100, size(tmpTable)) as OfferOrderQty1,rand(100, size(tmpTable)) as OfferOrderQty2,rand(100, size(tmpTable)) as OfferOrderQty3,rand(100, size(tmpTable)) as OfferOrderQty4,rand(100, size(tmpTable)) as OfferOrderQty5,rand(100, size(tmpTable)) as OfferOrderQty6,rand(100, size(tmpTable)) as OfferOrderQty7,rand(100, size(tmpTable)) as OfferOrderQty8,rand(100, size(tmpTable)) as OfferOrderQty9,rand(100, size(tmpTable)) as OfferOrders0,rand(100, size(tmpTable)) as OfferOrders1,rand(100, size(tmpTable)) as OfferOrders2,rand(100, size(tmpTable)) as OfferOrders3,rand(100, size(tmpTable)) as OfferOrders4,rand(100, size(tmpTable)) as OfferOrders5,rand(100, size(tmpTable)) as OfferOrders6,rand(100, size(tmpTable)) as OfferOrders7,rand(100, size(tmpTable)) as OfferOrders8,rand(100, size(tmpTable)) as OfferOrders9,rand(100, size(tmpTable)) as NumTrades,rand(100, size(tmpTable)) as IOPV,rand(100, size(tmpTable)) as TotalBidQty,rand(100, size(tmpTable)) as TotalOfferQty,rand(100, size(tmpTable)) as WeightedAvgBidPx,rand(100, size(tmpTable)) as WeightedAvgOfferPx,rand(100, size(tmpTable)) as TotalBidNumber,rand(100, size(tmpTable)) as TotalOfferNumber,rand(100, size(tmpTable)) as BidTradeMaxDuration,rand(100, size(tmpTable)) as OfferTradeMaxDuration,rand(100, size(tmpTable)) as NumBidOrders,rand(100, size(tmpTable)) as NumOfferOrders,rand(100, size(tmpTable)) as WithdrawBuyNumber,rand(100, size(tmpTable)) as WithdrawBuyAmount,rand(100, size(tmpTable)) as WithdrawBuyMoney,rand(100, size(tmpTable)) as WithdrawSellNumber,rand(100, size(tmpTable)) as WithdrawSellAmount,rand(100, size(tmpTable)) as WithdrawSellMoney,rand(100, size(tmpTable)) as ETFBuyNumber,rand(100, size(tmpTable)) as ETFBuyAmount,rand(100, size(tmpTable)) as ETFBuyMoney,rand(100, size(tmpTable)) as ETFSellNumber,rand(100, size(tmpTable)) as ETFSellAmount,rand(100, size(tmpTable)) as ETFSellMoney from tmpTable => Out of memory

请问在在mac上如何start DolphinDB server？
Got this error message:
ConnectionRefusedError: [Errno 61] Connection refused False
谢谢！