Both Are Great
Seriously. For most applications, either works fine.
Choose PostgreSQL When
Complex queries matter:
-- Window functions
SELECT name, salary,
AVG(salary) OVER (PARTITION BY department) as dept_avg
FROM employees;
-- CTEs (Common Table Expressions)
WITH active_users AS (
SELECT * FROM users WHERE active = true
)
SELECT * FROM active_users WHERE created_at > '2024-01-01';
Data integrity is critical:
- Better constraint support
- More strict by default
- Proper transaction isolation
JSON is central:
-- Query JSON fields
SELECT data->>'name' FROM products WHERE data->>'category' = 'electronics';
Choose MySQL When
Simplicity wins:
- Easier to get started
- More hosting options
- Larger community for common issues
Read-heavy workloads:
- Simple replication setup
- Good read performance out of the box
Team familiarity:
- If everyone knows MySQL, stick with it
Key Differences
| Feature | PostgreSQL | MySQL | |---------|------------|-------| | JSON | JSONB (binary, indexed) | JSON (text) | | Full-text search | Built-in | Built-in | | Replication | Streaming | Binary log | | Case sensitivity | Sensitive by default | Configurable |
Migration Tips
// PostgreSQL uses different column types
$table->boolean('active'); // real boolean, not tinyint
$table->jsonb('metadata'); // use jsonb, not json
// Case-sensitive by default
->where('email', $email) // exact match required
->whereRaw('LOWER(email) = ?', [strtolower($email)]) // case-insensitive
My Take
Start with PostgreSQL for new projects. It's more capable and the differences matter less for simple apps but become important as you grow.