Analyzing CREATE TABLE (PostgreSQL)

In the previous section, we wrote our first SQL query to create a table in PostgreSQL.

Now, let’s slow down a bit and understand what that SQL actually means.

We’ll break the query into parts and understand the syntax step by step.

The SQL We Wrote

create table cities (
  name varchar(50),
  country varchar(50),
  population integer,
  area integer
);

This single SQL statement created a table in our database.

Let’s understand how.

Keywords vs Identifiers

Every SQL statement is made up of different words.

These words fall into two main categories:

🔹 Keywords

• Special words defined by SQL
• They tell the database what action to perform

Examples:

• create
• table
• integer
• varchar

Keywords are usually written in uppercase (this is a convention, not a rule).

🔹 Identifiers

• Names that we choose
• Used to tell the database what to operate on

Examples:

• cities (table name)
• name, country, population, area (column names)

Identifiers are usually written in lowercase.

Breaking Down the Statement

1️⃣ create table cities

create table cities

This line tells PostgreSQL:

• create a new table
• name the table cities

At this point, PostgreSQL knows we want to create.