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 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. The default database used is SQLite and the database file is. This example will rename our existing employees table to _employees_old. Home Assistant uses database to store events and parameters for history and tracking. SELECT employee_id, last_name, first_name INSERT INTO employees (employee_id, last_name, first_name) fullschema Show schema and the content of sqlitestat tables. 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 When started, the sqlite3 program will show a brief banner message then prompt. 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 create the new employees table with the last_name field defined as a VARCHAR datatype. This example will rename our existing employees table to _employees_old. To show all columns of a table, you use the following steps: Login to the MySQL database server. 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 TABLE Show names of all indices If TABLE specified, only show indices for. The syntax to MODIFY A COLUMN in a table in SQLite is: PRAGMA foreign_keys=off ĪLTER TABLE table1 RENAME TO _table1_old userserver sqlite3 SQLite version 3.8.6 11:46:33 Enter. You can not use the ALTER TABLE statement to modify a column in SQLite.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |