How do I rename a column in a SQLite database table?

Note that as of version 3.25.0 released September 2018 you can now use ALTER TABLE to rename a column.

Original "create new and drop old table" answer below.

Say you have a table and need to rename "colb" to "col_b":

First create the new table with a temporary name, based on the old table definition but with the updated column name:

CREATE TABLE tmp_table_name (
  col_a INT
, col_b INT
);

Then copy the contents across from the original table.

INSERT INTO tmp_table_name(col_a, col_b)
SELECT col_a, colb
FROM orig_table_name;

Drop the old table.

DROP TABLE orig_table_name;

Last you rename the temporary table table to the original:

ALTER TABLE tmp_table_name RENAME TO orig_table_name;

Don't forget to re-create indexes, triggers, etc. The documentation gives a fuller picture of the gotchas and caveats.

Wrapping all this in a BEGIN TRANSACTION; and COMMIT; is also probably a good idea.

This was just fixed with 2018-09-15 (3.25.0)

Enhancements the ALTER TABLE command:

• Add support for renaming columns within a table using ALTER TABLE table RENAME COLUMN oldname TO newname.
• Fix table rename feature so that it also updates references to the renamed table in triggers and views.

You can find the new syntax documented under ALTER TABLE

The RENAME COLUMN TO syntax changes the column-name of table table-name into new-column-name. The column name is changed both within the table definition itself and also within all indexes, triggers, and views that reference the column. If the column name change would result in a semantic ambiguity in a trigger or view, then the RENAME COLUMN fails with an error and no changes are applied.

^{Image source: https://www.sqlite.org/images/syntax/alter-table-stmt.gif}

Example:

CREATE TABLE tab AS SELECT 1 AS c;

SELECT * FROM tab;

ALTER TABLE tab RENAME COLUMN c to c_new;

SELECT * FROM tab;

db-fiddle.com demo

Android Support

As of writing, Android's API 27 is using SQLite package version 3.19.

Based on the current version that Android is using and that this update is coming in version 3.25.0 of SQLite, I would say you have bit of a wait (approximately API 33) before support for this is added to Android.

And, even then, if you need to support any versions older than the API 33, you will not be able to use this.

Digging around, I found this multiplatform (Linux | Mac | Windows) graphical tool called DB Browser for SQLite that actually allows one to rename columns in a very user friendly way!

Edit | Modify Table | Select Table | Edit Field. Click click! Voila!

However, if someone want to share a programmatic way of doing this, I'd be happy to know!

CASE 1 : SQLite 3.25.0+

Only the Version 3.25.0 of SQLite supports renaming columns. If your device is meeting this requirement, things are quite simple. The below query would solve your problem:

ALTER TABLE "MyTable" RENAME COLUMN "OldColumn" TO "NewColumn";

CASE 2 : SQLite Older Versions

You have to follow a different Approach to get the result which might be a little tricky

For example, if you have a table like this:

CREATE TABLE student(Name TEXT, Department TEXT, Location TEXT)

And if you wish to change the name of the column Location

Step 1: Rename the original table:

ALTER TABLE student RENAME TO student_temp;

Step 2: Now create a new table student with correct column name:

CREATE TABLE student(Name TEXT, Department TEXT, Address TEXT)

Step 3: Copy the data from the original table to the new table:

INSERT INTO student(Name, Department, Address) SELECT Name, Department, Location FROM student_temp;

Note: The above command should be all one line.

Step 4: Drop the original table:

DROP TABLE student_temp;

With these four steps you can manually change any SQLite table. Keep in mind that you will also need to recreate any indexes, viewers or triggers on the new table as well.

Quoting the sqlite documentation:

SQLite supports a limited subset of ALTER TABLE. The ALTER TABLE command in SQLite allows the user to rename a table or to add a new column to an existing table. It is not possible to rename a colum, remove a column, or add or remove constraints from a table.

What you can do of course is, create a new table with the new layout, SELECT * FROM old_table, and fill the new table with the values you'll receive.

From the official documentation

A simpler and faster procedure can optionally be used for some changes that do no affect the on-disk content in any way. The following simpler procedure is appropriate for removing CHECK or FOREIGN KEY or NOT NULL constraints, renaming columns, or adding or removing or changing default values on a column.

1. Start a transaction.

2. Run PRAGMA schema_version to determine the current schema version number. This number will be needed for step 6 below.

3. Activate schema editing using PRAGMA writable_schema=ON.

4. Run an UPDATE statement to change the definition of table X in the sqlite_master table: UPDATE sqlite_master SET sql=... WHERE type='table' AND name='X';

   Caution: Making a change to the sqlite_master table like this will render the database corrupt and unreadable if the change contains a syntax error. It is suggested that careful testing of the UPDATE statement be done on a separate blank database prior to using it on a database containing important data.

5. If the change to table X also affects other tables or indexes or triggers are views within schema, then run UPDATE statements to modify those other tables indexes and views too. For example, if the name of a column changes, all FOREIGN KEY constraints, triggers, indexes, and views that refer to that column must be modified.

   Caution: Once again, making changes to the sqlite_master table like this will render the database corrupt and unreadable if the change contains an error. Carefully test of this entire procedure on a separate test database prior to using it on a database containing important data and/or make backup copies of important databases prior to running this procedure.

6. Increment the schema version number using PRAGMA schema_version=X where X is one more than the old schema version number found in step 2 above.

7. Disable schema editing using PRAGMA writable_schema=OFF.

8. (Optional) Run PRAGMA integrity_check to verify that the schema changes did not damage the database.

9. Commit the transaction started on step 1 above.

One option, if you need it done in a pinch, and if your initial column was created with a default, is to create the new column you want, copy the contents over to it, and basically "abandon" the old column (it stays present, but you just don't use/update it, etc.)

ex:

alter table TABLE_NAME ADD COLUMN new_column_name TYPE NOT NULL DEFAULT '';
update TABLE_NAME set new_column_name = old_column_name;
update TABLE_NAME set old_column_name = ''; -- abandon old column, basically

This leaves behind a column (and if it was created with NOT NULL but without a default, then future inserts that ignore it might fail), but if it's just a throwaway table, the tradeoffs might be acceptable. Otherwise use one of the other answers mentioned here, or a different database that allows columns to be renamed.

need to rename a few columns in some tables

Another way is to use multiple SQLite3 commands to "rename" a column, in "some" tables, repeat as needed:

.output tmp

SELECT "ALTER TABLE """|| sqlite_master.name ||""" RENAME COLUMN old_name TO new_name;" FROM sqlite_master 
WHERE type = "table" AND sqlite_master.name NOT LIKE 'sqlite_%';

.read tmp

source

Since version 2018-09-15 (3.25.0) sqlite supports renaming columns

https://sqlite.org/changes.html