![]() If you noticed from the above table where we have created the table and show the inserted records. We have used a DELETE term at first to delete the table name “mobile” and then applied the condition in the WHERE clause that deletes the record where MOBILE_ID is equal to “3”. In this example, we have a basic SQLite DELETE query with only one criterion in the WHERE clause. ![]() Sqlite > INSERT INTO mobile VALUES ( 6, 'Lenovo P2', 36900, '9023312', 'non-Approved' ) Īs from SQLite select query, we can see the new entry in the table “mobile.”The following record we have inserted above is shown in the table.Įxample 1: Using SQLite DELETE With the Condition Sqlite > INSERT INTO mobile VALUES ( 5, 'Infinix Zero X', 49999, '4091172', 'Approved' ) Sqlite > INSERT INTO mobile VALUES ( 3, 'Tecno Spark', 24999, '9012675', 'Approved' ) Inside the table “mobile,” the column names are set as MOBILE_NAME, MOBILE_PRICE, MOBILE_CODE, and STATUS with the different data types. Then, we can use the SQLite delete statement to delete the records from the rows, and we can also delete the table. Columns with a false or NULL expression are retained.įirst, we have created the following table as “mobile” in SQLite. Only the entries over which the WHERE clause’s Boolean is valid are eliminated when a WHERE clause is given. ![]() All data from the table is erased if the WHERE condition is not found. The DELETE command, in essence, removes data from the table identified by the provided table name. When the WHERE clause is removed, the entire table is deleted. Here, the supplied table name refers to the actual table that exists in the database, and the specified search condition refers to the actual WHERE clause condition that we must apply to the table to delete it. We used a delete statement and specified some attributes to delete values from the table, as you can see in the SQLite Delete statement above. I guess anyway that the SQL tool that you used edits the SQLite table directly in the same way than DB Browser for SQLite without going through the GDAL driver and therefore does not update the feature_count.DELETE FROM table_name WHERE I did not test the QGIS Execute SQL method because I found a few slightly different Execute SQL tools from the processing toolbox but none of them looked alike your screen capture. The count got updated immediately in the table of contents during the editing session and the change was permanent when I stopped editing and saved the edits. QGIS also updated the feature count for me when I deleted some features from the attribute table by selecting and pressing Del or by using the Delete selected feature button. ogrinfo test.gpkg -sql "delete from test where id=100" I made a test by deleting one feature with ogrinfo and the feature_count was correctly updated. The GDAL GPKG driver understands the meaning of the extra metadata table and feature_count field. The gpkg_ogr_metadata table does not have triggers for guarding the integrity and adding such trigger would probably be a bad idea because the table is not used by other programs than GDAL. WHERE type = 'table' AND name = 'gpkg_ogr_contents' ĬREATE TABLE gpkg_ogr_contents(table_name TEXT NOT NULL PRIMARY KEY,feature_count INTEGER DEFAULT NULL) The structure of the table can be checked from sqlite_master: SELECT sql FROM sqlite_master Therefore GDAL creates an additional metadata table gpkg_ogr_contents from where the feature count can be fetched directly. GDAL and QGIS want to know how many features there are on a layer but SELECT COUNT(*) is slow for big tables.
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