PostgreSQL Fetch Data
Learn how to retrieve data from PostgreSQL tables using the SELECT statement and its most common clauses.
The SELECT Statement
SELECT is the workhorse of SQL: it retrieves rows from one or more tables. In its simplest form, you list the columns you want, followed by the table to read from. Using an asterisk (*) selects every column in the table.
Select all columns from a table
SELECT * FROM customers;Select specific columns
SELECT full_name, email
FROM customers;Filtering with WHERE
The WHERE clause filters rows so only those matching a condition are returned. Conditions can compare column values using operators like =, <>, <, >, and combine multiple conditions with AND, OR, and NOT.
Filter rows with a condition
SELECT full_name, signup_date
FROM customers
WHERE signup_date >= '2026-01-01';Sorting and Limiting Results
ORDER BY controls the order in which rows are returned, either ascending (ASC, the default) or descending (DESC). LIMIT restricts how many rows come back, which is useful for previewing data or building paginated results.
- WHERE filters which rows are included in the result
- ORDER BY sorts the result set by one or more columns
- LIMIT caps the number of rows returned
- OFFSET skips a number of rows, often paired with LIMIT for pagination
- DISTINCT removes duplicate rows from the result set
Exercise: PostgreSQL Fetch Data
When combining LIMIT and OFFSET, what does OFFSET control?
