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Oracle ADB: rename the service_name connect_data

By Franck Pachot . Since Aug. 4, 2020 we have the possibility to rename an Autonomous Database (ATP, ADW or AJD – the latest JSON database) on shared Exadata infrastructure (what was called ‘serverless’ last year which is a(…)

Oracle Database Appliance and CPU speed

Introduction A complaint I heard from customers about ODA is the low core speed of the Intel Xeon processor embedded in the X8-2 servers: Intel(R) Xeon(R) Gold 5218 CPU @ 2.30GHz. 2.30GHz only? Because of its comfortable number of cores(…)

Amazon DynamoDB: the cost of indexes

By Franck Pachot . That’s common to any data structure, whether it is RDBMS or NoSQL, indexes are good to accelerate reads but slow the writes. This post explains the consequences of adding indexes in DynamoDB. Secondary Indexes What(…)

Installing MariaDB Server 10.5.5 on CentOS 8

In the following blog, you will learn how to install the latest version of the MariaDB Server 10.5.5 on CentOS 8 and how to use the mariadb user & binaries instead of mysql.

Merge-Statement crashes with ORA-7445 [kdu_close] caused by Real Time Statistics?

In a recent project we migrated an Oracle database previously running on 12.1.0.2 on an Oracle Database Appliance to an Exadata X8 with DB version 19.7. Shortly after the migration a merge-statement (upsert) failed with an ORA-07445: exception encountered:(…)

Amazon DynamoDB Local: running NoSQL on SQLite

By Franck Pachot . DynamoDB is a cloud-native, managed, key-value proprietary database designed by AWS to handle massive throughput for large volume and high concurrency with a simple API. simple API: Get, Put, Query, Scan on a table without(…)

RDBMS (vs. NoSQL) scales the algorithm before the hardware

By Franck Pachot . In The myth of NoSQL (vs. RDBMS) “joins dont scale” I explained that joins actually scale very well with an O(logN) on the input tables size, thanks to B*Tree index access,(…)

A lesson from NoSQL (vs. RDBMS): listen to your users

By Franck Pachot . I have written a few blog posts about some NoSQL (vs. RDBMS) myths (“joins dont scale”, “agility: adding attributes” and “simpler API to(…)

SQL Server Installation Wizard error : Failed to retrieve data for this request

Today I faced a strange issue when I tried to install a new SQL Server instance : Failed to retrieve data for this request This error occurred just after clicking on “New SQL Server stand-alone installation…”(…)

ODA: odacli now supports Data Guard in 19.8

Introduction I’ve been dreaming of this kind of feature: just because most of the ODA configurations now include Disaster Recovery capabilities, through Data Guard or Dbvisit standy. If Dbvisit will obviously never be integrated to odacli, the lack of Data(…)