Useful tips for everyday
How are procedures and functions handled in Oracle? Oracle can process procedures and functions as well as individual SQL statements. A procedureor functionis a schema…
What is the difference between Db2 and MySQL? MySQL is an open-source relational database management system (RDBMS) based on Structured Query Language (SQL)….Difference between MySQL…
How do I sum multiple rows in access? Add a Total row Make sure that your query is open in Datasheet view. To do so,…
What is PostgreSQL rules? The PostgreSQL rule system allows one to define an alternative action to be performed on insertions, updates, or deletions in database…
Does Composite have a primary key? A composite key specifies multiple columns for a primary-key or foreign-key constraint. The next example creates two tables. The…
Do database schemas change frequently? These are unfortunately frequent and necessary, especially when introducing new features to existing applications. Schema changes can be performed in…
Does Union all return unique rows? UNION Example The following statement combines the results of two queries with the UNION operator, which eliminates duplicate selected…
How do you list records with dates in the last 10 days? The standard ANSI SQL format would be: SELECT Table. date FROM Table WHERE…
How many columns in a table affect query performance? CASE 1: I have a table with 30 columns and I query using 4 columns in…
How to set up a database logging log? Set up database logging 1 Go to System administration > Setup > Database log > Database log…