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How to get ROWID in SQLite?

sql
join
best-practices
data-retrieval
Anton ShumikhinbyAnton Shumikhin·Oct 25, 2024
TLDR

To fetch the unique ROWID in SQLite, use the following query:

SELECT ROWID, * FROM table_name;

Just replace table_name with the actual name of your table. This will return a list including the ROWID for each row. The aliases rowid, oid, and _rowid_ are interchangeable, except in the case of an INTEGER PRIMARY KEY column.

Fetching rows based on conditions

You can extract rows meeting certain conditions with a WHERE clause in your query:

SELECT ROWID, * FROM table_name WHERE column_name = 'desired_value';

Where column_name is the name of your column and desired_value is the condition value.

Important points to note

  • The rowid won't appear when using PRAGMA table_info or .schema. It's an invisible column, but it's always there.
  • Even with AUTOINCREMENT, SQLite still uses rowid for maintaining uniqueness.
  • It's usually not advisable to change the rowid, as it could impact the relational data's integrity.

Understanding the magic of rowid

In SQLite, the ROWID acts like the address of a record. It's a smart mechanism for quick data retrieval. The intended role here is similar to the unique ID of a book in a library system, which speeds up the access to any book.

Exploiting ROWID in SQL queries

Deletion of specific rows

Got an unwanted row? Make it disappear like a magic trick:

DELETE FROM table_name WHERE ROWID = 3;

// Talk about cleaning out your bookshelf!

Updating specific rows

ROWID makes updating specific rows as easy as swapping out old books for new ones:

UPDATE table_name SET column_name = 'new_value' WHERE ROWID = 2;

// The "New Shelf, Who Dis?" maneuver 📚

Joining tables with ROWID

ROWID is like a universal friend-maker you can use when joining tables:

SELECT a.ROWID, b.* FROM table_a a JOIN table_b b ON b.foreign_key = a.ROWID;

// It's the "book club" of SQL, introducing books (tables) to each other 🤝

The "dos" and "don'ts" of using ROWID

Don'ts:

  • Don't use rowid for tables declared WITHOUT ROWID.
  • Avoid modifying rowid to prevent the rise of unexpected side effects.
  • Never consider rowid as permanent. It may change, especially after a VACUUM operation.

Dos:

  • Leverage the fast accessibility property of rowid.
  • Use ROWID for debugging processes. It can serve as a stethoscope to examine low-level data issues.
  • Do remember: rowid can be your last resort for recovering corrupted or lost data.