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How do you maintain a database schema?
Make the developers who have been creating or altering the schemas willy-nilly go via the DBA. Create a single source-controlled DDL/SQL script for each release and only use it to update the databases.
Why do we need schema in database?
Database schemas are important because they help developers visualize how a database should be structured. A project may only use a few tables and fields. Still, having a schema gives developers a clear point of reference about what tables and fields a project contains.
Why do we need a schema?
Schemas can be useful because they allow us to take shortcuts in interpreting the vast amount of information that is available in our environment. Schemas can contribute to stereotypes and make it difficult to retain new information that does not conform to our established ideas about the world.
How do I make SQL more powerful?
Supercharge Your SQL Queries for Production Databases
- Define business requirements first.
- SELECT fields instead of using SELECT *
- Avoid SELECT DISTINCT.
- Create joins with INNER JOIN (not WHERE)
- Use WHERE instead of HAVING to define filters.
- Use wildcards at the end of a phrase only.
- Use LIMIT to sample query results.
What do you need to know about database maintenance?
Database Maintenance is a term we use to describe a set of tasks that are all run with the intention to improve your database. There are routines meant to help performance, free up disk space, check for data errors, check for hardware faults, update internal statistics, and many other obscure (but important) things.
How often should a database integrity check be run?
But this is where the Integrity Check comes into play. The Database Integrity Check examines and analyzes the database in its entirety, and can detect and repair most any corruption it comes across. The database integrity check should be run on a regular, reoccurring, weekly schedule.
What are the elements of a double entry accounting system?
In a double-entry bookkeeping system, the basic elements are accounts and transactions. The basic ‘theory’ is the accounting equation: Equity = Assets – Liabilities.
What should I do if something happens to my database?
Using these log files, you can actually restore a database to the state it was at any point in time before. So if something bad happens to your database (either corruption, accidentally, or maliciously), you can recover your data as it was the instant before the event happened.