PostgreSQL bytea

A PostgreSQL column type that stores raw bytes inline in a table row. The equivalent of MySQL's BLOB.

Properties ​

• Standard SQL interface (INSERT, UPDATE, SELECT).

• No storage overhead: PostgreSQL stores the raw bytes as-is on disk.

• Transfer overhead only: Client must escape binary data for the SQL wire protocol. The DB decodes it back before storing.

• Uses TOAST internally (1 GB per entry, 4 billion entries per table).

• Entire value loaded into server memory on read. No partial reads or seeking.

When to Use ​

• Small to medium binary files (under a few MB).

• You want a simple SQL interface without OID tracking.

bytea vs text for File Storage ​

• bytea is for binary data. No encoding assumptions.

• text is for character data (UTF-8 validated). No encoding overhead for actual text. Gives you string operations (LIKE, regex, full-text search) for free.

• For plain text files, text is the natural choice. For binary files, bytea.