First of all let’s explain the acronym. SQL stands for Structured Query Language and is a programming language that was created to handle data within relational databases consisting of columns and rows.
Today SQL is one of the most popular database management languages and, due to its simplicity, there is a range of quality open source variants. Accessing multiple data records using SQL is easy. A single command is all it takes and it doesn’t need an index. Instead SQL uses declarative statements to make complex queries due to the richness of its language.
SQL works by using different elements that all consist of a “statement”. Statements, commonly known as queries, begin with terms such as select or create and use a semicolon to confirm the end of the query.
Here are some of the typical elements that SQL incorporates:
Clauses: statements like “UPDATE” and “WHERE”.
Expressions: these can result in scalar values containing columns and rows.
Predicates: these indicate things that can change a query. Entering “BETWEEN” or “ALL” will offer different results.
Queries: these bring up the data requested.
Statements: these deliver queries to the database server through your SQL software and use terms such as “SELECT” and “CREATE”.
Here are some examples of useful SQL queries:
Alter Table: Allows you to add new columns to increase the different types of data the database can hold.
Create Table: This adds new tables allowing the database to hold further data.
Order By: allows you to order your information in a manner that is useful.
Update: This lets you change your database as needed.
SQL’s versatility means it is the ideal choice for many companies doing heavy work with databases where they need to change that data and results. At EDC4IT we have experts on hand to provide you or your company with the training necessary to maintain your databases as necessary. Just check out our database courses and let us know if we can tailor one to suit your specific needs.