So, we can easily find all the constraints on the table in Oracle using data dictionary views. We can then take whatever action like modify, disable, or drop, we want to take on these constraints. Constraints are enforcing data integrity rules in the Oracle database and we must be careful...
There could be data in the table which violates an unvalidated constraint. So the database can no longer rely on it to optimize some operations. For example, usingconstraints to get better execution plans. To overcome this it's good practice to validate constraints. This ensures all existing r...
While Oracle Database can combine B-trees (via a "bitmap conversion from rowids"), this is relatively expensive. In general to get the same performance as the three bitmaps, you need to place all three columns in a single index. This affects how reusable an index is, which we'll come...
Planned downtime is a preventive or corrective maintenance task that interrupts day-to-day system operations. Usually, due to constraints that are imposed by the system's software and hardware design, this downtime cannot be delayed. Planned downtime should be scheduled to minimally impact the ava...
Once you disable constraint, then later you might need to enable again, but during this exercise make sure that all your data changes are correct. PostgreSQL does not provide any direct command or function to disable / enable the Foreign key constraints. ...
walk you through the need for Oracle and Snowflake and then explore two methods for migration: manual migration and using automated tools. By the end, you’ll have a clear understanding of how to seamlessly transition from Oracle to Snowflake, no matter your expertise level. Let’s dive in...
All the bug fixes supplied by the above SRUs are addressed in the initial Oracle Solaris 11.1 SRU. This SRU is in Support Repository. The update steps that are required might be different due to some systems running different SRU versions. To find out what SRU is on a system, you can ...
Querying Data at a Point in Time (Flashback Query)Although some Oracle tools and applications simplify or mask the use of SQL, all database operations are performed using SQL, to take advantage of the security and data integrity features built into Oracle.Overview...
Using the Oracle Application Express development environment, you can quickly build an application that enables a user to view and update information stored in an Oracle Database.This tutorial describes how to create and deploy an application that tracks the assignment, status, and progress of ...
Drop foreign key constraints and secondary indexes; disable triggers When we settle on the schema that we want on the target, we have to prepare it for migrating the actual data from the source. We will be using the AWS Database Migration Service (AWS DMS). DMS has two phases: full loa...