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1. SQLITE INSERT DUPLICATE TO UNIQUE HOW TO
2. SQLITE INSERT DUPLICATE TO UNIQUE UPDATE
3. SQLITE INSERT DUPLICATE TO UNIQUE FULL
4. SQLITE INSERT DUPLICATE TO UNIQUE CODE

However, my question is: Is there a way to only add to a table rows that are unique? Here - correctly - none of the rows were inserted, because all were duplicates. #> Error: UNIQUE constraint failed: iris.row If you manually create a table using DBI::dbSendQuery(), you can specify a primary key my understanding is that this makes it so that duplicate rows cannot be added (by adding as a constraint that there are no duplicated primary keys): library(DBI) One challenge I've encountered concerns inserting duplicate rows.Īs in the following reprex, it's easy to (advertently or not) add duplicate rows: library(DBI)

SQLITE INSERT DUPLICATE TO UNIQUE HOW TO

In this tutorial, we have shown you how to use the SQLite REPLACE statement to insert or replace a row in a table.I am interested in creating and populating a SQLite database via R. If the title column does not have the NOT NULL constraint, the REPLACE statement will insert a new row whose the title column is NULL. Therefore, SQLite rolls back the transaction. However, it violates the NOT NULL constraint of the title column. Then, SQLite tried to insert a new row with two columns: ( id, min_salary).

SQLITE INSERT DUPLICATE TO UNIQUE UPDATE

What the statement tried to do is to update the min_salary for the position with id 2, which is the developer.įirst, the position with id 2 already exists, the REPLACE statement removes it.

SQLITE INSERT DUPLICATE TO UNIQUE CODE

VALUES( 2, 110000) Code language: SQL (Structured Query Language) ( sql ) Notice that the REPLACE statement means INSERT or REPLACE, not INSERT or UPDATE. Third, SQLite inserted a new row with the data provided by the REPLACE statement. Second, because this statement violated the UNIQUE constraint by trying to add the DBA title that already exists, SQLite deleted the existing row. REPLACE INTO positions (title, min_salary)Ĭode language: SQL (Structured Query Language) ( sql )įirst, SQLite checked the UNIQUE constraint. Positions Code language: SQL (Structured Query Language) ( sql )

You can verify the REPLACE operation using the SELECT statement. VALUES( 'Full Stack Developer', 140000) Code language: SQL (Structured Query Language) ( sql ) REPLACE INTO positions (title, min_salary)

SQLITE INSERT DUPLICATE TO UNIQUE FULL

The following REPLACE statement inserts a new row into the positions table because the position title Full Stack Developer is not in the positions table. Suppose, you want to add a position into the positions table if it does not exist, in case the position exists, update the current one. ON positions (title) Code language: SQL (Structured Query Language) ( sql ) The following statement creates a unique index on the title column of the positions table to ensure that it doesn’t have any duplicate position title: CREATE UNIQUE INDEX idx_positions_title SELECT * FROM positions Code language: SQL (Structured Query Language) ( sql ) Third, verify the insert using the following SELECT statement. ( 'Architect', 150000) Code language: SQL (Structured Query Language) ( sql ) INSERT INTO positions (title, min_salary) Second, insert some rows into the positions table. ) Code language: SQL (Structured Query Language) ( sql ) The SQLite REPLACE statement examplesįirst, create a new table named positions with the following structure. Let’s take a look at some examples of using the SQLite REPLACE statement to understand how it works. Or in a short form: REPLACE INTO table(column_list) VALUES(value_list) Code language: SQL (Structured Query Language) ( sql ) INSERT OR REPLACE INTO table(column_list) The following illustrates the syntax of the REPLACE statement. In the second step, if any constraint violation e.g., NOT NULL constraint occurs, the REPLACE statement will abort the action and roll back the transaction.

Summary: in this tutorial, you will learn how to use the SQLite REPLACE statement to insert or replace the existing row in a table.