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Database / SQLite Interview questions

What is the PRAGMA statement used for?

PRAGMA is SQLite's mechanism for querying or modifying internal engine settings and behavior — configuration knobs that aren't part of standard SQL but control how SQLite itself operates for the current connection or database.

PRAGMA foreign_keys = ON;      -- enable foreign key enforcement
PRAGMA journal_mode = WAL;     -- switch to write-ahead logging mode
PRAGMA table_info(person);     -- inspect a table's column definitions
PRAGMA integrity_check;        -- verify database file consistency

Some pragmas are per-connection settings that reset each time you reconnect (like foreign_keys), while others persist as part of the database file itself (like journal_mode = WAL). Because there's no separate configuration file or server settings panel the way client-server databases have, pragmas are how essentially all of SQLite's tunable behavior is accessed.

What is PRAGMA used for in SQLite?
Do all pragma settings persist across reconnecting to the database?

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