What is SQL?
Structured Query Language (SQL) is standard computer language relational database management and data manipulation.
Used to query, insert, update and modify data.
We pronounce it as ''sequel'' or S-Q-L.
Used to communicate with database.
Statements are made up of descriptive words and are easy to learn.
SQL is a non procedural language:
- We cannot use it to write complete applications.
- It's simple, but very powerful.
How is SQL used?
- SQL is all about data !
- Read and retrieve data
- Write data - add data to a table
- Update data - insert new data.
Who Uses SQL?
- Backend Developer
- QA Engineer
- Database Admin (DBA)
- Data Analyst
- System Admin
- Data Architect
- ETL Developer
- Systems Engineer
- Data Scientist
Database Administrator Vs Data Scientist:
Database Administrator:
- Manages/governs entire database.
- Gives permissions to users.
- Determine access to data,
- Manages and creates tables.
- Uses SQL to query and retrieve data.
Data Scientist:
- End user of a database.
- Uses SQL to query and retrieve data.
How do Data Scientists uses SQL?
- Retrieve data.
- Combine multiple sources together.
- Write complex queries for analysis.
- May create their own table or test environment.
SQL and Database Management System:
what you're writing may change a little bit based on the relational database management system you're using. you can think of SQL as the interpreter between you and the database. How you write some of the syntax for SQL is going to depend on the relational database management system you're interacting with. Extending our analogy you can think of this as the accent or maybe as the dialect. SQL is able to translate it for you, but sometimes you have to tweak it a little bit based on the database management system you're using. Here are some of the popular ones, SQL Server, PostgreSQL, MySQL.
Tags:
Database/SQL