SQL stands for Structured Query Language. SQL is used to communicate with a database. According to ANSI (American National Standards Institute), it is the standard language for relational database management systems.
SQL statements are used to perform tasks such as update data on a database, or retrieve data from a database.
Some common relational database management systems that use SQL are: Oracle, Microsoft SQL Server, Access, Ingres, etc. Although most database systems use SQL, most of them also have their own additional proprietary extensions that are usually only used on their system. However, the standard SQL commands such as "Select", "Insert", "Update", "Delete", "Create", and "Drop" can be used to accomplish almost everything that one needs to do with a database.
Microsoft SQL Server is used to store information with the combination of rows and columns.
Before we start building SQL statements in SQL Server, we need to understand what the basic parts of a statement are. Overall, a “statement” is something you write in SQL to get an answer from a database or to make a change to it.
DML stands for Data Manipulation Language statements. These are statements that read, add, edit or remove data
DDL stands for Data Definition Language statements. These are statements that related to objects, such as tables, in SQL Server vs data. For example, to create a table, you would use a CREATE TABLE statement, specifying the name and other attributes of your table. Later you could use DML statements to add data to it, update or remove that data, and read the data
Clauses are the basic components of SQL statements, the smaller building blocks that make up the whole. These clauses are constructed out of keywords, which tell the database to take a specific action. There are also field names, which tell the database where to look and what to look for. There are also predicates, which let us specify what information we’re working with. Predicates include a value or condition called an expression. A clause can be a statement if you’re writing a really basic one. There are also operators, as we’ll see later on, which let us compare equality or ranges of data or treat information in other ways.