database-replication

问题 People, the company where I work has some MySQL databases on AWS (Amazon RDS). We are making a POC with BigQuery and what I am researching now is how to replicate the bases to BigQuery (the existing registers and the new ones in the future). My doubts are: How to replicate the MySQL tables and rows to BigQuery. Is there any tool to do that (I am reading about Amazon Database Migration Service)? Should I replicate to Google Cloud SQL and than export to BigQuery? How to replicate the future

问题 People, the company where I work has some MySQL databases on AWS (Amazon RDS). We are making a POC with BigQuery and what I am researching now is how to replicate the bases to BigQuery (the existing registers and the new ones in the future). My doubts are: How to replicate the MySQL tables and rows to BigQuery. Is there any tool to do that (I am reading about Amazon Database Migration Service)? Should I replicate to Google Cloud SQL and than export to BigQuery? How to replicate the future

问题 Using postgres source connector in kafka. It works properly for some time and suddently stops with above error. Please assist if someone knows this issue. 回答1: This happens if the database is not available and the only way to fix it to restart the connector. I would advise you to check the database logs and see if database is going down or refusing connection to Kafka Connect 来源： https://stackoverflow.com/questions/60450498/org-apache-kafka-connect-errors-connectexception-an-exception

问题 MySQL server seems to constantly lock up and stop responding on certain types of queries and eventually (after couple of minutes of not responding) give up with an error " MySQL server has gone away ", then hang again on the next set of queries, again and again. The server is set up as a slave to replicate from a master to dbA , mostly INSERT statements, around 5-10 rows per second. A PHP based application is running on the server that reads the freshly replicated data every 5-10 seconds,

问题 We are setting up a database on three different Postgresql servers (and maybe on more in the future), currently syncing all tables using bucardo multi-master groups. We are not syncing sequences; we tried that, and we noticed bucardo is making us lose data when simultaneous writes occur in the same table, on different servers. Since they use the same keys, on sync time bucardo chooses to drop one of the duplicate rows. Our current approach is to manually namespace the sequence on each

问题 We are setting up a database on three different Postgresql servers (and maybe on more in the future), currently syncing all tables using bucardo multi-master groups. We are not syncing sequences; we tried that, and we noticed bucardo is making us lose data when simultaneous writes occur in the same table, on different servers. Since they use the same keys, on sync time bucardo chooses to drop one of the duplicate rows. Our current approach is to manually namespace the sequence on each

问题 I have a 3 member replica set. Read preference is set as "Secondary Preferred" How to check application is reading from Secondary Node in MongodB? Please suggest. 回答1: Firstly you can configure profiling. For that you need to start your mongodb servers with option --profile 2 and configure log file. It'll log all queries. After that you can read log for each instance db. Simple example: db.your_collection.profile.find({ns: "name_your_db.your_collection"}) Secondly you can use mongotop . You

问题 I have a 3 member replica set. Read preference is set as "Secondary Preferred" How to check application is reading from Secondary Node in MongodB? Please suggest. 回答1: Firstly you can configure profiling. For that you need to start your mongodb servers with option --profile 2 and configure log file. It'll log all queries. After that you can read log for each instance db. Simple example: db.your_collection.profile.find({ns: "name_your_db.your_collection"}) Secondly you can use mongotop . You

问题 I know that Cassandra have different read consistency levels but I haven't seen a consistency level which allows as read data by key only from one node. I mean if we have a cluster with a replication factor of 3 then we will always ask all nodes when we read. Even if we choose a consistency level of one we will ask all nodes but wait for the first response from any node. That is why we will load not only one node when we read but 3 (4 with a coordinator node). I think we can't really improve

问题 I have an application set up with transactional replication being pushed to a standby machine that will be used for emergency failovers. The replication appears to be working, any inserts made to Server 1 will automatically appear at Server 2. However, I can't quite get the failover working. In the scenario that Server 1 becomes unavailable (which is the only scenario where Server 2 will ever be used, so the replication is one-way), the idea is that work should continue at Server 2, and that