What is Ad Hoc Query?

sql adhoc-queries
zihado picture zihado · Mar 17, 2010 · Viewed 166.7k times · Source

I'm reading a book about SQL. In that book there's the term Ad Hoc Query, which I don't understand.

What exactly is an ad hoc query?

Answer

David Hedlund picture David Hedlund · Mar 17, 2010

Ad hoc is latin for "for this purpose". You might call it an "on the fly" query, or a "just so" query. It's the kind of SQL query you just loosely type out where you need it

var newSqlQuery = "SELECT * FROM table WHERE id = " + myId;

...which is an entirely different query each time that line of code is executed, depending on the value of myId. The opposite of an ad hoc query is a predefined query such as a Stored Procedure, where you have created a single query for the entire generalized purpose of selecting from that table (say), and pass the ID as a variable.

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