![]() ![]() Query compositionality (AKA common table expressions) By and large, ORMs can only represent relatively basic read/write operations, whereas a proper query language can express much more:Ĭoalescing and defaults ( ? in JavaScript) For example, if your main query uses the Products table, but your variable points to a query that uses the Orders table, you’ll need to include a join to Orders in your main query.įor an example, see the documentation on Referencing models and saved questions in SQL queries.Hopefully it’s clear from the examples above, but in terms of expressive power, the query builder is beyiond every ORM we’re aware of. This means that your main query must be aware of all the tables that your variable is pointing to, otherwise you’ll get a SQL syntax error. When you run a query that includes a variable, the query will be executed by replacing the tag with the SQL query of the referenced question or model. If the SQL syntax of your query doesn’t match the SQL dialect used by your database, your database won’t be able to run the query. Any results or errors displayed in Metabase are the same as the results or errors that you would get if you ran the query directly against your database. When you run a query from the SQL editor, Metabase sends the query to your database exactly as it is written. #PSEQUEL QUERY WRITER CODE#You can use SQL snippets to save, reuse, and share SQL code across multiple questions that are composed using the SQL editor. Writing SQL queries that use variables or parameters can be very powerful, but it’s also a bit more advanced, so that topic has its own page if you’d like to learn more. ![]() Filter widgets let you modify the SQL query before it’s run, changing the results you might get. Queries are crucial because they empower coders to access, manipulate or organize data within a database. If you or someone else wrote a SQL query that includes variables, that question might have filter widgets at the top of the screen above the editor. You can also refer to models and saved questions in your SQL queries. Questions asked using SQL can be saved, downloaded, converted to models, and added to dashboards just like questions asked using the query builder. You can also run only part of a query by highlighting the part you’d like to run before clicking the run button or using the run shortcut key. That acronym, SEQUEL, was later changed to SQL, because SEQUEL was already trademarked by an airplane company, and companies really don't like getting into trademark lawsuits. And the first version was called SEQUEL, and it stood for Structured English QUEry Language. #PSEQUEL QUERY WRITER WINDOWS#You can run your SQL query by pressing ctrl + enter on Windows and Linux, or ⌘ + return on a Mac. So what's the deal Well, SQL was originally invented at IBM in the early 1970s. You’ll notice that the table that comes back is the same as if you had used the query builder to ask for the sum of Subtotal in the Orders table, grouped by the Created At date. Click the blue Run query button to execute your query. To try it out, make sure you’ve selected the Sample Database, then paste in this short SQL query:ĭon’t worry if you don’t understand this just yet. ![]() If you have the permissions to use the SQL editor, you’ll see an option to start a new SQL query next to a little console icon.Īfter clicking SQL query, you’ll see an editor where you can write and run queries in SQL (or your database’s native querying language). #PSEQUEL QUERY WRITER HOW TO#We won’t try to teach you all about SQL right now, but to learn more about it, check out Working with SQL.Įven if you don’t understand SQL or how to use it, it’s worthwhile to get an idea of how it works inside Metabase, because sometimes other people will share SQL-based questions that might be useful to you. people argue about this) stands for Structured Query Language, and is a widely used standard for getting data from databases. Make an easy decision based on library popularity, security and maintenance scores. SQL (pronounced “sequel”, or sometimes as S.Q.L. Choose the best JavaScript MySQL Query Builder library for your project. If you ever need to ask questions that can’t be expressed using the query builder, you can use SQL instead. ![]()
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