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Continue reading →: Oracle Database: Global Stats Changes After Partition TruncateI may be late to the party on this one, but it certainly surprised me during a database migration from Oracle 11G to Oracle 19.26 recently (yes, there’s a surprising amount of databases still on 11G – released in 12 years ago, and 10G, and even 9i, 8i, 8.0 and…
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Continue reading →: ORA-04021 timeout occurred while waiting to lock object during stats gatherI recently came across an interesting change in behaviour when gathering stats. Patch 32781163 (Deadlock on library cache lock on MV refresh and dbms_stats gathering the same object) was applied to an Oracle 19C system, and as well as curing the deadlock problem the client was experiencing it also changed…
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Continue reading →: Infinity – Old Oracle NumbersA long time ago, Oracle had a couple of special numbers that you were allowed to store in a NUMBER datatype. They were Infinity and Negative Infinity! If you selected these numbers (using SQL*Plus) , they showed up as “~” and “-~“, although it is worth noting that if you’re…
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Unlocking Insights: Why Conferences Matter
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Continue reading →: Unlocking Insights: Why Conferences MatterI very much enjoy speaking at conferences, and talking to everyone there. The insights that you get into how other companies are running their systems is incredible. The innovative approaches that different people and companies have to solving the same problems never ceases to amaze me, and the only way…
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Continue reading →: Fundamental Security Part Nine – Scripted PasswordsOctober 2024 – Oracle 19C, 23ai So a while ago I spoke about passwords but forgot to mention a key element of account control in the blog. I was giving a talk on Security a few days ago and told an audience member that this information was in my blog.…
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Oracle Data Migration Validation
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Continue reading →: Oracle Data Migration ValidationData migration is common. Moving data from one database to another, either via Datapump, Goldengate, unload/load scripts or some other method has risk. You are going to have to check. Frequently, I see the rows being counted. Any nothing else. If we have 10 rows in the source, and 10…
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Continue reading →: Hint ClassificationsIn my previous post, I wrote about the time I made a mistake specifying a hint via a SQL Patch, meaning it “didn’t work”. This leads to an understanding about the classification of hints – some hints are used for the Optimizer/CBO, but other hints have different reasons for being…
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Continue reading →: SQL Patch, and a Parallel mistakeJuly 2024. Oracle 19c, 23ai There are 3 main types of SQL Plan Management: So first some quick background info about the 3 options and then I’ll tell you about my mistake. SQL Profile A SQL Profile is a collections of hints to be applied to a SQL statement. It…
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Continue reading →: Time Zones and Oracle Database PatchingI have worked with several clients who rely heavily on time zone data and processing it correctly. If you have columns in your database which are defined as TIMESTAMP WITH TIME ZONE, you need to understand what the relevance is relating to the time zone in your database. For example,…
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Continue reading →: Oracle Statistics Gathering TimeoutJanuary 2024 – Oracle 12C, 19C, 21C, 23C+ Gathering object statistic in Oracle is important. The optimizer needs metadata about the object, such as the amount of rows and number of distinct values in a column, to help it decide the optimum way to access your data. This takes effort,…
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Continue reading →: Fundamental Security Part Eight – Unified AuditJanuary 2024 – Oracle 19C+ If you are Oracle 12.1 onwards, and you have not explicitly disabled it, you are using Unified Audit We previously discussed Data Encryption At Rest. Now lets talk about Unified Audit, and why you should be using it When you create an Oracle database, there…
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Continue reading →: Fundamental Security Part Seven– Data Encryption At RestOctober 2023 – Oracle 19C+ What is Data Encryption At Rest and why should we use it? We have looked at Data Encryption in Transit, encrypting your network traffic. Everyone should be doing this. But what about Encrypting Data At Rest? Data that is stored permanently (on your hard drives).…
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Continue reading →: Fundamental Security Part Six– Network EncryptionAugust 2023 – Oracle 19C We have considered observability. Knowing where you may have a security problem. We now need to look at removing some of the main problems associated with Oracle databases. Lets start with Network Security. By default, all data travelling over the network with Oracle is unencrypted.…
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Continue reading →: Fundamental Security Part Five – ObservabilityJuly 2023 – Oracle 19C Now you know what permissions have been granted in your system and to whom, as shown in the previous post. Maybe you have remediated them down to least privilege. Now, how do you ensure the system stays like that? How do you know if you…
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Continue reading →: Fundamental Security Part Four – Permissions CheckingJuly 2023 – Oracle 19C So in the previous post we talked about identifying unused and historic accounts. Old accounts should be removed, but what are the capabilities of the existing users who are accessing the systems? A surprisingly large amount of applications request that the schema owner, and maybe…
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