![]() Parametersĭatabase ( path-like object) – The path to the database file to be opened. connect ( database, timeout = 5.0, detect_types = 0, isolation_level = 'DEFERRED', check_same_thread = True, factory = sqlite3.Connection, cached_statements = 128, uri = False ) ¶ How to use the connection context managerĮxplanation for in-depth background on transaction control. How to convert SQLite values to custom Python types How to adapt custom Python types to SQLite values Just a helper.How to use placeholders to bind values in SQL queries You'll find a reference to a query() function. Sql = "INSERT INTO " t " SELECT " cols " FROM xfer" Sql = "CREATE TABLE " t cols_w_types ")" Sql = "INSERT INTO xfer SELECT " cols " FROM " t Sql = "CREATE TEMPORARY TABLE xfer " cols_w_types ")" # Build the strings, filtering for the column to throw outĬols_w_types = r " " r " PRIMARY KEY," # Initialize two strings: one for column names column types and one just list of columns to junk: columns_to_junkĭef removeColumns(db_cur, t, columns_to_junk):.MSqliteCommand = new SQLiteCommand (mSql, mSqliteDbConnection) This code also preserves the Primary key and Foreign key.ĬODE in C#: void RemoveColumnFromSqlite (string tableName, string columnToRemove) _backup" Just in case if it could help someone like me.īased on the Official website and the Accepted answer, I made a code using C# that uses NuGet package. The SQL used has the drawback that autoincrement columns are not preserved. In contrast to other answers, the SQL used in this approach seems to preserve the data types of the columns, whereas something like the accepted answer seems to result in all columns to be of type TEXT. "CREATE TABLE `t1_backup` AS SELECT `$columns` FROM `$tableName` ĪLTER TABLE `t1_backup` RENAME TO `$tableName` ") Column does not exist in table, no need to do anything. If(strtolower($row->name) != strtolower($columnName)) $rows = $statement->fetchAll(PDO::FETCH_OBJ) $statement = $pdo->prepare("PRAGMA table_info($tableName) ") Determine all columns except the one to remove. Public function DropTableColumn($tableName, $columnName) * string $columnName The column to remove from the table. * string $tableName The table to remove the column from. In case anyone needs a (nearly) ready-to-use PHP function, the following is based on this answer: /** SDML = ( _T("DROP TABLE MyOriginalTable_old ") ) ĮxecDML( StringOps::tstringTo_stdString(_T("commit transaction ")).c_str() ) SDML = StringOps::std_sprintf(_T("ALTER TABLE TempTable1 RENAME TO MyOriginalTable\n") ) ![]() ![]() ![]() SDML = StringOps::std_sprintf(_T("ALTER TABLE MyOriginalTable RENAME TO MyOriginalTable_old\n") ) SDML = StringOps::std_sprintf(_T("insert into TempTable1 SELECT %s FROM MyOriginalTable \n"), sFieldNamesSeperatedB圜ommas.c_str() ) ĮxecDML( StringOps::tstringTo_stdString(sDML).c_str() ) SFieldNamesSeperatedB圜ommas.erase( int(sFieldNamesSeperatedB圜ommas.size()) - 1 ) If ( sFieldNamesSeperatedB圜ommas.at( int(sFieldNamesSeperatedB圜ommas.size()) - 1) = _T(',')) SFieldNamesSeperatedB圜ommas = (sColNameCurr _T(",")) If ( pvsColsToDelete->at(nColsToDelete) = sColNameCurr ) GetTableColNames( _T("MyOriginalTable"),
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