If you’re using the SQLite database and another user imports a large volume of data, labeling might slow down for other users on the server due to the database load. See Start Label Studio Slowness while labeling Then it will insert all of the data from the _employees_old table into the employees table.To resolve this issue, update the host specified as an environment variable or when starting Label Studio. Then it will create the new employees table with the hire_date field called start_date. This example will rename our existing employees table to _employees_old. INSERT INTO employees (employee_id, last_name, first_name, start_date) Let's look at an example that shows how to rename a column in a SQLite table.Īnd we wanted to rename the hire_date field to start_date, we could do the following: PRAGMA foreign_keys=off The syntax to RENAME A COLUMN in a table in SQLite is: PRAGMA foreign_keys=off Instead you will need to rename the table, create a new table, and copy the data into the new table. You can not use the ALTER TABLE statement to rename a column in SQLite. Then it will insert all of the data (excluding the hire_date field) from the _employees_old table into the employees table. Then it will create the new employees table with the hire_date field removed. SELECT employee_id, last_name, first_name INSERT INTO employees (employee_id, last_name, first_name) Let's look at an example that shows how to drop a column in a SQLite table.įor example, if we had an employees table that was defined as follows: CREATE TABLE employeesĪnd we wanted to drop the column called hire_date, we could do the following: PRAGMA foreign_keys=off The syntax to DROP A COLUMN in a table in SQLite is: PRAGMA foreign_keys=off You can not use the ALTER TABLE statement to drop a column in a table. Then it will insert all of the data from the _employees_old table into the employees table. Then it will create the new employees table with the last_name field defined as a VARCHAR datatype. SELECT employee_id, last_name, first_name, hire_date INSERT INTO employees (employee_id, last_name, first_name, hire_date) ( employee_id INTEGER PRIMARY KEY AUTOINCREMENT,Īnd we wanted to change the datatype of the last_name field to VARCHAR, we could do the following: PRAGMA foreign_keys=off ĪLTER TABLE employees RENAME TO _employees_old ![]() Let's look at an example that shows how to modify a column in a SQLite table.įor example, if we had an employees table that had a column called last_name that was defined as a CHAR datatype: CREATE TABLE employees The syntax to MODIFY A COLUMN in a table in SQLite is: PRAGMA foreign_keys=off ĪLTER TABLE table1 RENAME TO _table1_old ![]() ![]() You can not use the ALTER TABLE statement to modify a column in SQLite.
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