719:. For this to work, every time the user downloads a page, a unique identifier must be chosen and added as a query string to the URLs of all links the page contains. As soon as the user follows one of these links, the corresponding URL is requested to the server. This way, the download of this page is linked with the previous one.
23:
is a part of a uniform resource locator (URL) that assigns values to specified parameters. A query string commonly includes fields added to a base URL by a Web browser or other client application, for example as part of an HTML document, choosing the appearance of a page, or jumping to positions in
929:
and store the parameters in the request body. The length limits on request bodies are typically much higher than those on URL length. For example, the limit on POST size, by default, is 2 MB on IIS 4.0 and 128 KB on IIS 5.0. The limit is configurable on Apache2 using the
707:
A program receiving a query string can ignore part or all of it. If the requested URL corresponds to a file and not to a program, the whole query string is ignored. However, regardless of whether the query string is used or not, the whole URL including it is stored in the server
62:
path or by handling the request using logic that is specific to the type of resource. In cases where special logic is invoked, the query string will be available to that logic for use in its processing, along with the path component of the URL.
892:
Different query strings passed by different visits to the page will mean that the pages are never served from the browser (or proxy, if present) cache thereby increasing the load on the web server and slowing down the user
882:
Query strings form part of the URL, and are therefore included if the user saves or sends the URL to another user; cookies can be maintained across browsing sessions, but are not saved or sent with the
348:
element is deprecated and most browsers no longer support or render it, there are still some vestiges of indexed search in existence. For example, this is the source of the special handling of
910:
Various ad hoc limitations on request-line length are found in practice. It is RECOMMENDED that all HTTP senders and recipients support, at a minimum, request-line lengths of 8000 octets.
91:
may provide methods for parsing multiple parameters in the query string, separated by some delimiter. In the example URL below, multiple query parameters are separated by the
852:
The addition of the query string does not change the way the page is shown to the user. When the user follows, for example, the first link, the browser requests the page
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If the user arrives at the same web server by two (or more) independent paths, it will be assigned two different query strings, while the stored cookies are the same.
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to deal with this problem, while HTML forms make some additional substitutions rather than applying percent encoding for all such characters. SPACE is encoded as '
889:
The user can disable cookies, in which case using cookies for tracking does not work. However, using query strings for tracking should work in all situations.
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specifies the following transformation for submitting HTML forms with the "GET" method to a web server. The following is a brief summary of the algorithm:
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attribute. This was intended to allow web servers to use the provided text as query criteria so they could return a list of matching pages.
871:, making it possible to establish that all these pages have been viewed by the same user. Query strings are often used in association with
253:. Web forms may include fields that are not visible to the user; these fields are included in the query string when the form is submitted.
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directive, which specifies the number of bytes from 0 (meaning unlimited) to 2147483647 (2 GB) that are allowed in a request body.
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cannot be part of a URL (for example, the space) and some other characters have a special meaning in a URL: for example, the character
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element as a single-line text-input control. The text entered into this control was sent to the server as a query string addition to a
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The exact structure of the query string is not standardized. Methods used to parse the query string may differ between websites.
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query strings in URLs within HTML documents without having to entity escape ampersands. Since 2014, W3C recommends to use only
376:' (as per section 4.4 of CGI 1.1). Some CGI scripts still depend on and use this historic behavior for URLs embedded in HTML.
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When a server receives a request for such a page, it may run a program, passing the query string, which in this case is
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When the text input into the indexed search control is submitted, it is encoded as a query string as follows:
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The query string is composed of a series of arguments by parsing the text into words at the spaces.
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These facts allow query strings to be used to track users in a manner similar to that provided by
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501:
representation with any non-ASCII characters first encoded as UTF-8 (or other specified encoding)
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The form content is only encoded in the URL's query string when the form submission method is
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recommendation. In the recommendations of 1999, W3C recommended that all web servers support
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The main differences between query strings used for tracking and HTTP cookies are that:
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This way, any subsequent page request from this user will carry the same query string
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in the above example) will receive the following query string:
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defines three ways a user agent can generate the query string:
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https://example.com/path/to/page?name=ferret&color=purple
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as expected, adding the query string to its links as well.
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One of the original uses was to contain the content of an
1036:
T. Berners-Lee; R. Fielding; L. Masinter (January 2005).
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T. Berners-Lee; R. Fielding; L. Masinter (January 2005).
311:
request for the base URL or another URL specified by the
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Part of a URL that assigns values to specified parameters
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If the URL is too long, the web server fails with the
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A typical URL containing a query string is as follows:
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field1=value1&field2=value2&field3=value3...
921:The common workaround for these problems is to use
312:
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1241:. Httpd.apache.org. Retrieved on 2013-09-08.
228:While there is no definitive standard, most
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449:–
447:A
442:'
436:+
412:+
404:=
396:#
374:=
354:+
338:+
248:=
218:;
216:"
199:=
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