nosql

Restoring data to couchbase due to fresh couchbase installation

由 有些话、适合烂在心里 提交于 2019-12-12 16:33:16
问题 We have a couchbase server that somehow had a fresh installation and all our data that was there is lost. I had managed to take the backup of /opt/couchbase/var/lib/couchbase/data/ … Now when i try to copy the data back it is not showing the couchbase server.Any help is appreciated. 来源： https://stackoverflow.com/questions/49644532/restoring-data-to-couchbase-due-to-fresh-couchbase-installation

MongoDB find on all properties of document

由 泪湿孤枕 提交于 2019-12-12 16:17:58
问题 How do I create a query in mongodb to filter by any property of the document. I have a collection of objects as follows: { "_id" : ..., "name" : "John", "city" : "Rio de Janeiro", "state" : "RJ", "address" : "Street 1, .... " } I have on my page a field that allows a user to retrieve pro records in any column. If it was MYSQL I find the names of all the columns in the table and create a clause 'OR' searching for 'LIKE' the value entered by the user. Is there any easy way to do this with

Sum Query in Elasticsearch

由 余生长醉 提交于 2019-12-12 14:12:59
问题 I'm fairly new to Elasticsearch. I'm trying to write a query that will group by a field and calculate a sum. In SQL, my query would look like this: SELECT lane, SUM(routes) FROM lanes GROUP BY lane I have this data that looks like this in ES: { "_index": "kpi", "_type": "mroutes_by_lane", "_id": "TUeWFEhnS9q1Ukb2QdZABg", "_score": 1.0, "_source": { "warehouse_id": 107, "date": "2013-04-08", "lane": "M05", "routes": 4047 } }, { "_index": "kpi", "_type": "mroutes_by_lane", "_id": "owVmGW9GT562

This document does not exist, it will not appear in queries or snapshots? Cloud Firestore

由 坚强是说给别人听的谎言 提交于 2019-12-12 13:31:16
问题 I'm quite new to Cloud Firestore (aren't we all?) and I've added some data to my db using the admin SDK in Node.js. It shows up on the console, but under the doc it says "This document does not exist, it will not appear in queries or snapshots." I'm not sure why this is? Here's a screenshot: 回答1: The key thing to realize is that just because you create a document at root_collection > root_doc > sub_collection > sub_doc does not mean there is actually a document at root_collection > root_doc .

HBase>HBase概述

由 感情迁移 提交于 2019-12-12 13:23:27
文章目录 1、HBase基本介绍 2、HBase与Hadoop的关系 1、HDFS 2、HBase 3、RDBMS与HBase的对比 1、关系型数据库 2、HBase 4、HBase特征简要 5、HBase的基础架构 1、HBase基本介绍 简介 hbase是bigtable的开源java版本。是 建立在hdfs之上 ，提供高可靠性、高性能、列存储、可伸缩、实时读写nosql的 数据库系统 。 它介于nosql和RDBMS之间，仅能通过主键(row key)和主键的range来检索数据，仅支持单行事务(可通过hive支持来实现多表join等复杂操作)。 主要用来存储结构化和半结构化的松散数据。 Hbase查询数据功能很简单，不支持join等复杂操作，不支持复杂的事务（行级的事务） Hbase中支持的数据类型：byte[] 与hadoop一样，Hbase目标主要依靠 横向扩展 ，通过不断增加廉价的商用服务器，来增加计算和存储能力。 HBase中的表一般有这样的特点： 大：一个表可以有上十亿行，上百万列 面向列:面向列(族)的存储和权限控制，列(族)独立检索。 稀疏:对于为空(null)的列，并不占用存储空间，因此，表可以设计的非常稀疏。 传统数据表 官方网站： http://hbase.apache.org 2、HBase与Hadoop的关系 1、HDFS 为分布式存储提供文件系统

Create two composite columns with cassandra-cli

由 吃可爱长大的小学妹 提交于 2019-12-12 13:03:41
问题 My column family needs two composite columns, the key data type is BytesType. Here is the definition of table using CQL: CREATE TABLE stats ( gid blob, period int, tid blob, sum int, uniques blob, PRIMARY KEY(gid, period, tid) ); What I want to do is to create the column family but with Cassandra CLI. Here is my shot. The structure of the first composite is: CompositeType(Int32Type, BytesType, AsciiType) and it will holds an integer. The structure of the second composite is: CompositeType

NoSQL and meteorological data

由 北城以北 提交于 2019-12-12 11:32:29
问题 So there's this new cool thing, these NoSQL-databases. And so there's my data: Rows of rows of rows of meteorological data: Values, representing certain measurements at a certain station (Identified by a WMO number, not coordinates), at a certain time. Not every station measures every parameter, not every parameter is measured all the time. I store this data (30 years worth of hourly values, resulting in ~1 billion values) currently in MySQL. The continous growth and the forseeable addition

Migrate data from relational DB to NoSQL

由 南笙酒味 提交于 2019-12-12 11:05:39
问题 Is it possible/are there tools/ best practices etc to migrate data to a NoSQL format from a relational DB. I have a JEE6 app making use of Hibernate ORM to persist to MySQL but now we wish to move to NoSQL solution but need to bring the existing data with us Thanks W 回答1: There are some tools to help the migration, but in the end, MySQL is a relational database which has a completely different structure from noSQL databases. In the end, you will almost always have to do these four steps

Do you know some good resources for learning NoSQL databases? [closed]

由 南笙酒味 提交于 2019-12-12 10:56:27
问题 As it currently stands, this question is not a good fit for our Q&A format. We expect answers to be supported by facts, references, or expertise, but this question will likely solicit debate, arguments, polling, or extended discussion. If you feel that this question can be improved and possibly reopened, visit the help center for guidance. Closed 7 years ago . I consider to use some NoSQL database in one of my project. Do you know some good starting points for a newbie in this topic? 回答1:

Get aggregate sum of json array in Postgres NOSQL json data

由 穿精又带淫゛_ 提交于 2019-12-12 10:39:28
问题 How to get aggregate SUM(amount) from " refunds " array in postgres json select Following is my data schema and structure: Table Name: transactions Column name: data { "id": "tran_6ac25129951962e99f28fa488993", "amount": 1200, "origin_amount": 3900, "status": "partial_refunded", "description": "Subscription#sub_a67d59efb2bcbf73485a ", "livemode": false, "refunds": [ { "id": "refund_ee4192ffb6d2caa490a1", "amount": 1200, "status": "refunded", "created_at": 1426412340, "updated_at": 1426412340,
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