![]() ![]() Update data: When this option is checked, SQL Update statements are generated. Ignore existing records: During an import and when this option is checked, records that already exist in the table are ignored.Įmpty the table before importing: When this is checked you tell the SQLite Adapter to empty the contents of the table prior to running the import, effectively deleting all existing rows. Insert data: When this option is checked, SQL Insert statements are generated. When the Adapter is being used on the WRITE side (right-hand side), in the lower half of this tab you can specify what actions the SQLite Adapter should take during an import (insert/update) into the SQLite database. data types), only missing table fields are inserted. Note: No fields are deleted or existing fields amended (e.g. ![]() Insert missing fields automatically into tables: When this option is checked, the SQLite table schema is adjusted to the actual fields listed in the SQLite Adapter. Note: If this option is checked, you must manually enter a table name into the "Fields / Data types" tab. Note: The password is stored in the Definition data in encrypted form.Ĭreate a database if it does not exist: If this option is checked, when the SQLite database in the specified folder does not already exist, a new (empty) SQLite database will be created.Ĭreate tables if they do not exist: This option informs the SQLite Adapter to generate new tables in the SQLite database if they are not already available. If you want to store the password it is necessary to check the "Save Password" option here. If the database is protected with a password, you can optionally enter it here. SQLite Adapter - configure database propertiesYou specify the path (absolute or relative) to the SQLite database here. However, amending existing table fields is not supported. It is also possible with the SQLite Adapter to extend existing tables with new fields. One feature of the SQLite Adapter is to support creation of new SQLite databases (files) and tables. Note: The Adapter supports SQLite version 3. ON DUPLICATE KEY UPDATE is non-destructive, in that it will only ever issue INSERT or UPDATE statements, but never DELETE.įor example, we have decided we wish to replace our id = 1 record of Green Eggs and Ham and revert it back to the original In Search of Lost Time record instead.The SQLite Adapter makes it possible to import into, export from or update records in an SQLite database. Unlike REPLACE – an inherently destructive command due to the DELETE commands it performs when necessary – using INSERT. ON DUPLICATE KEY UPDATE statement and clause. The alternative (and generally preferred) method for INSERTING into rows that may contain duplicate UNIQUE or PRIMARY KEY values is to use the INSERT. More information on using REPLACE can be found in the official documentation. Notice that even though we only altered one row, the result indicates that two rows were affected because we actually DELETED the existing row then INSERTED the new row to replace it. ![]() Seuss', 1960 ) Query OK, 2 rows affected ( 0. Mysql > REPLACE INTO books ( id, title, author, year_published ) VALUES ( 1, 'Green Eggs and Ham', 'Dr. The obvious purpose is to execute a large number of INSERT statements for a combination of data that is both already existing in the database as well as new data coming into the system.įor example, our books table might contain a few records already: This means that an INSERT IGNORE statement which contains a duplicate value in a UNIQUE index or PRIMARY KEY field does not produce an error, but will instead simply ignore that particular INSERT command entirely. Using INSERT IGNORE effectively causes MySQL to ignore execution errors while attempting to perform INSERT statements. MySQL provides a number of useful statements when it is necessary to INSERT rows after determining whether that row is, in fact, new or already exists.īelow we’ll examine the three different methods and explain the pros and cons of each in turn so you have a firm grasp on how to configure your own statements when providing new or potentially existing data for INSERTION. ![]()
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