Confirm error updating person information and exit.Ĭonsole.WriteLine("Error updating person information.") Confirm successful updating of person information.Ĭonsole.WriteLine("Person information updated successfully.") Query text incorporated into SQL command. Message confirming unsuccessful database connection.Ĭonsole.WriteLine("Database connection unsuccessful.") Message confirming incorrect database location.Ĭonsole.WriteLine("Error locating database.") Ĭonnect = new SqliteConnection("Data Source=" + database + " " + The declaration and execution of the SQL statement is wrapped in a ‘try-catch-finally’ block to catch any errors that may arise and close the database connection at the end. The SQL statement is then executed and a confirmation message is displayed. The other parameters are for updating the ‘lastname’ and ‘title’ fields against the record. One of the parameters is for an ‘id’, so that only the specified record is updated, in this case, the record with an ‘id’ of five. If successfully found, a connection to the database is established, then the query parameters are defined as variables, which are bound in to the SQL statement. If it doesn’t, a message is displayed and execution of the program is halted. Firstly, a check is made to see if the database file actually exists. Updating data follows the same pattern as inserting data. The following example updates the record in the ‘person’ table that was added in the example for inserting data. Serial.In order to update data in an SQLite database, the SQL ‘Update’ statement needs to be used. for: ON CONFLICT (mac_id) DO UPDATE set type=? for:INSERT INTO test_table (mac_id,status,type) VALUES (?, ?, ?) for:UPDATE daily_temp_ap set status=? WHERE mac_id=? Sqlite3_exec(db1, "BEGIN TRANSACTION", NULL, NULL, &zErrMsg) Serial.printf("ERROR preparing sql: %s\n", sqlite3_errmsg(db1)) Rc = sqlite3_prepare_v2(db1, sql, strlen(sql), &res, &tail) "INSERT INTO test_table (mac_id,status,type) VALUES (?, ?, ?)" "INSERT INTO test_table (mac_id,sensor_type,status) VALUES (?, ?, ?) ON CONFLICT (mac_id) DO UPDATE set status=?" Rc = db_exec(db1, "CREATE TABLE IF NOT EXISTS test_table (mac_id DATETIME NOT NULL PRIMARY KEY UNIQUE, status INTEGER, type INTEGER)") ĭisplayPrompt("No. "CREATE TABLE IF NOT EXISTS test_table1 (mac_id INTEGER NOT NULL PRIMARY KEY, U1 INTEGER, U2 INTEGER, U3 INTEGER, U4 INTEGER, U5 INTEGER, U6 INTEGER, U7 INTEGER, U8 INTEGER, U9 INTEGER, U10 INTEGER)" "CREATE TABLE IF NOT EXISTS test_table (mac_id DATETIME NOT NULL PRIMARY KEY UNIQUE, status INTEGER, type INTEGER)" Serial.println(F("Failed to mount file Serial")) ĭisplayPrompt("No. Static int callback(void *data, int argc, char **argv, char **azColName) This example demonstrates how SQLite behavesĪt first it asks how much memory to occupyĬonst char* data = "Callback function called" This is the code I used for testing, based on the "bulk_data_insert" example: /* But now and than I will have to insert a new row. Has anyone a suggestion how to speed this up? I will mostly do updates. Any idea how I could improve this? I am still new to sqlite and c++ programming. I will only get 22 rows per second (I am not using any Indexes). However if I add "ON CONFLICT (mac_id) DO UPDATE set type=?": INSERT INTO test_table (mac_id,type,status) VALUES (?, ?, ?) ON CONFLICT (mac_id) DO UPDATE set status=? Or update more than 800 rows per second with: UPDATE test_table set status=? WHERE mac_id=? I can insert more than 800 rows per second in a database with: INSERT INTO test_table (mac_id,status,type) VALUES (?, ?, ?) I have used the "bulk_data_insert" example, adding "BEGIN TRANSACTION" / "END TANSACTION" and I am using a SPI SD card (WEMOS MINI D1 ESP32 with SD shield) instead of a SD MMC configuration.
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