![]() On the other hand, the ability to put an arbitrary string in the query allows one to pass whole code blocks into a template. The sqlsafe keyword indicates that the user (you) is confident that no code injection is possible and takes responsibility for simply putting whatever string is passed in the parameters directly into the query. Custom connectors Easily extend Power Query by creating your own connectors and data transformations if you need to, that can also easily be shared and used by others. For batch processes, it should not be an issue, but using the sqlsafe construct in web applications could be dangerous. Power Query works across several Microsoft products, so whatever you learn for Power Query in Excel can be applied to Power BI and other products. One important caveat is the risk of code injection. Just press the capture key (F1 or Option-F1) to import a Web page, mail messages, the selected items in Evernote or other apps, or any file on your Mac.: EagleFiler libraries use an open format: regular files and folders that are fully accessible to your other applications.Skip importing duplicate files and remove duplicate messages from mailboxes. Because the details of parameter substitution are hidden, one can focus on building the template and the set of parameters and then call a single function to get the final SQL. With the helper functions above, creating and running templated SQL queries in python is very easy. In JinjaSql, the corresponding template would simply become select user_id, count(*) as num_transactions, sum(amount) as total_amount from transactions where user_id = clauses and could be removed. If we want to run the query above for an arbitrary user and date, we need to parameterize the user_id and the transaction_date values. Here, we assume that the database will automatically convert the YYYY-MM-DD format of the string representation of the date into a proper date type. To compute the number of transactions and the total amount for a given user on a given day, a query directly to the database may look something like select user_id, count(*) as num_transactions, sum(amount) as total_amount from transactions where user_id = 1234 and transaction_date = '' group by user_id The columns in this table could be transaction_id, user_id, transaction_date, and amount. Let’s assume we have a table transactions holding records about financial transactions. Besides many powerful features of Jinja2, such as conditional statements and loops, JinjaSql offers a clean and straightforward way to parameterize not only the values substituted into the where and in clauses, but also SQL statements themselves, including parameterizing table and column names and composing queries by combining whole code blocks. Without going into comparing different approaches, this post explains a simple and effective method for parameterizing SQL using JinjaSql. ![]() There are numerous situations in which one would want to insert parameters in a SQL query, and there are many ways to implement templated SQL queries in python.
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