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SQL will give you the ability to do important data work yourself, making you more appealing to employers.
SQL and Python are developed to perform different tasks. SQL, or Structured Query Language, is a query language primarily used to query and retrieve data from tables within a database. SQL is not designed to manipulate or transform data into other formats. Python is a general-purpose programming language that can analyze and manipulate data, and is widely used today to develop applications, artificial intelligence, etc. using its tools and libraries.
Yes, SQL is easy to learn! Its English-based syntax makes it very easy to understand. SQL is not a mathematical language like Matlab, so you don’t have to be a tech-person to understand it. It uses simple English words such as SELECT, INSERT, UPDATE, and DELETE as its commands, which make it very easy if you know basic English. Also, most database engines are compatible with the SQL code.
SQL stands for “Structured Query Language”. It is a query language used to add, alter, update, or delete data from tables in a database using simple English-based commands. On the other hand, MySQL is a relational database management system (RDBMS). MySQL is an open-source platform that uses SQL.
The answer isn’t necessarily the same for everyone. As a beginner, you might need more time to grasp the basic concepts of SQL. Once you learn to make your way through it and get to the intermediate level, you can learn faster. On an average, you may expect to learn the basics of SQL in about two to three weeks. After that, if you want to dive deeper, it would take longer to master your skills. Remember, everyone has a different learning pace, and it’s OK to take your time.
CHAR has a fixed size. If you assign, say, 20 bytes, it will always take up 20 bytes in the database, even if you store data of lesser size, say, 4 bytes. You should use CHAR only if you know the exact length of the string.
VARCHAR2 size depends on how many bytes you actually store in the database, say, 4 bytes. The size you assign, say, 20 bytes, is just the maximum number of bytes that can be stored in that variable. You should use VARCHAR2 when you don't know the exact length of stored strings, or it will waste disk space.