What is Ad Hoc Query?

Question

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 1

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.

Answer 2

An Ad-Hoc Query is a query that cannot be determined prior to the moment the query is issued. It is created in order to get information when need arises and it consists of dynamically constructed SQL which is usually constructed by desktop-resident query tools.

Check: http://www.learn.geekinterview.com/data-warehouse/dw-basics/what-is-an-ad-hoc-query.html

Answer 3

Also want to add that ad hoc query is vulnerable to SQL injection attacks. We should try to avoid using it and use parameterized SQLs instead (like PreparedStatement in Java).

Answer 4

An Ad-Hoc Query is a query that cannot be determined prior to the moment the query is issued. It is created in order to get information when need arises and it consists of dynamically constructed SQL which is usually constructed by desktop-resident query tools. An ad hoc query does not reside in the computer or the database manager but is dynamically created depending on the needs of the data user.

In SQL, an ad hoc query is a loosely typed command/query whose value depends upon some variable. Each time the command is executed, the result is different, depending on the value of the variable. It cannot be predetermined and usually comes under dynamic programming SQL query. An ad hoc query is short lived and is created at runtime.

Answer 5

Ad hoc queries are those that are not already defined that are not needed on a regular basis, so they're not included in the typical set of reports or queries

Answer 6

Ad hoc query is type of computer definition. Which means this query is specially design to obtain any information when it is only needed. Predefined. refer this https://www.youtube.com/watch?v=0c8JEKmVXhU

Answer 7

An Ad-Hoc query is:

1. Pre-planned question.
2. Pre-scheduled question.
3. spur of the moment question.
4. Question that will not return any results.

Answer 8

In Sql Server "Ad Hoc Query" is also used for Ad Hoc Distributed Queries. These are ad hoc queries on an other server via OpenRowset or OpenDatasource. Ad Hoc Distributed Queries are only allowed after configuring so. This is a Server configuration option.