![]() This is where you have to trick and kill two birds with one stone by adding a. an array with the unique row found for a "SELECT" query by identifier.an array with the list of rows for a "SELECT" query returning multiple lines.all() to do everything, it will actually give: ![]() an array of "rows" that contains the rows returned by the query.all() method also provides 2 objects to its callback function : a Result object that contains the result returned by the executed query and information about the execution of this query.an Error object (according to the "error-first" pattern popularized by Node).query() method of the node-postgres module always returns 2 objects to the callback function that it chains: Pool.query("SELECT * FROM Books WHERE Books_ID = $1",, callback) Pool.query("UPDATE Books SET Title = $1 WHERE Book_ID = $2",, callback) Just like we do with node-postgres: pool.query("CREATE TABLE Books. ",, callback) ĭb.all("UPDATE Books SET Title = $1 WHERE Book_ID = $2",, callback) ĭb.all("SELECT * FROM Books WHERE Books_ID = $1",, callback) We can therefore write without any problem: db.all("CREATE TABLE Books. ![]() the "SELECT" for an identifier: it seemed obvious. ![]() all() method from the SQlite3 module, because it handles perfectly: query() method.Īfter some tests, we can always use the. While on the node-postgres side, everything is done with a single. get() for SELECTs by identifier that return a single line all() to perform SELECTs that return multiple rows It's even better, because that way you're sure you haven't forgotten a parameter by mistake. Pool.query("SELECT * FROM Books",, callback) īut this time, the SQlite3 module is very flexible and we can do exactly as with node-postgres : db.get("SELECT * FROM Books WHERE Books_ID = $1",, callback) ĭb.all("SELECT * FROM Books",, callback) Similarly, when it's not a parameterized query, the SQlite3 module allows the parameter to be completely zapped, whereas the node-postgres module requires an empty array: db.all("SELECT * FROM Books", callback) Whereas for the node-postgres module, it's imperative that it be within an array: pool.query("SELECT * FROM Books WHERE Books_ID = $1",, callback) When there is only one SQL parameter, the SQlite3 module accepts that this unique data is transmitted as a value, and not within an array: db.get("SELECT * FROM Books WHERE Books_ID = $1", id, callback) db.run("UPDATE Books SET Title = $1 WHERE Book_ID = $2",, callback) Query.pool("UPDATE Books SET Title = $1 WHERE Book_ID = $2",, callback) īut this is absolutely not a problem, because the SQlite database supports very well parameters in the form "$1, $2, $3. db.run("UPDATE Books SET Title = ? WHERE Book_ID = ?",, callback) When you go to PostgreSQL, you see more like "$1, $2, $3. " to identify parameters in parameterized queries. Generally, examples for SQlite use "?, ?, ?.
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