In the previous article on XML, we looked at such an outdated way of validating XML documents, the XML DTD. This method is still used to validate XML data, but every day it is being replaced more and more by a new technology called XML Schema. Many shortcomings in XML schemas have been fixed, which were in the XML DTD, so at the moment all leading developers use only XML schemas for document validation.
To appreciate the advantages of XML Schema over DTDs, let's take a closer look at the main DTD weaknesses that have been successfully corrected in XML Schemas. I already mentioned them in the article "", but for a better understanding, let's repeat.
Disadvantages of XML DTDs over XML Schema
- Language syntax other than XML. That is, the DTD is not XML. This can lead to a variety of problems with encoding and verifying XML documents.
- No data type checking. There is only one data type in XML DTDs - string. In this regard, for example, if there is text in a numeric field, the document will still be verified, since the XML DTD cannot check the data type.
- You cannot map more than one Description DTD to a single XML document. That is, a document can be verified with only one DTD description. If there are several of them, then you will have to redo the descriptions and combine everything in one file, which is very inconvenient.
These were the main shortcomings of the XML DTD, which were successfully corrected in the industry standard for describing XML documents, XML Schema.
XML Schema - the industry standard for describing XML documents
In short, XML Schema does the following:
- Describes the names of elements and attributes (dictionary).
- Describes the relationship between elements and attributes and their structure (content model).
- Describes data types.
I also want to note that at the moment, using diagrams, you can describe almost everything. That is, a schema is a universal way of describing a data grammar that can be used not only for verifying XML documents, but also for describing databases, etc. Thus, the scope of application of the schemes is very wide at the moment.
XML Schema Example for XML Document Validation
As practice shows, the material is much better assimilated if you immediately start studying with examples. I must say right away that we will not delve into all the subtleties, since the material is very complex, especially if you study it in text form.
Simple XML Schema Example
Using this schema, you can validate an XML document with the following content.
<книга xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation = "book.xsd"> <название>XML basics <цена>300
So, back to our XML schema. As you have already noticed, XML already known to us is used to create XML schemas. The only difference here is that XML Schema already defines elements, unlike regular XML. Because of this, namespaces are used. In this case, the required namespace is "http://www.w3.org/2001/XMLSchema", which will be prefixed with "xs".
I want to note right away that you can use both namespace prefixes and set the namespace for the root element. As such, there is no difference here. Everyone decides for himself how to act in a given situation. I will just say that the prefixes "xs" or "xsd" are usually used.
Well, now let's figure out how to decipher the above scheme. As mentioned above, XML Schema is a description of a dictionary and data types. Based on this, we will decipher each element.
As you can see, there is nothing super complicated here. If you think about it, everything is very simple.
Basic XML Schema Elements
In short, XML schema can be described as follows.
As you can see from the example, each XML schema consists of a root element "schema" and a required namespace "http://www.w3.org/2001/XMLSchema". The following is a description of the circuit and the circuit itself. At the same time, very often in very high-quality schemas, the description is much larger than the XML Schema itself.
Description of elements in XML Schema
At the beginning of the article, we have already looked at an example of the simplest XML schema. In it, we separately described elements and types. At the same time, I want to note right away that the sequence does not play a role here. The circuit will work anyway.
Now let's look at the second way to write XML Schema, which is based on describing the type immediately inside the element. This method is suitable if you do not plan to use the same description for different elements. For clarity, consider an example.
As you can see from the example, the element is declared using the special construction "element" using the appropriate prefix. In this case, we define an element named "root" without specifying a type (type), since it will be described inside the element. That is, there are two ways to describe items.
1 way
2 way
You can use both the first method and the second. They all work the same way. The only question is convenience in this particular case.
Further, after declaring the element, we indicate that it is of a complex type (
As you can see, everything is pretty simple so far. Again, we will not go into all the details, since this article is intended to familiarize yourself with XML Schema, and not study it in detail.
How XML Schema and Document Mapping
The peculiarity of XML Schema is that it does not describe the document itself, but the namespace. In this regard, most often there is no mention of her in the document. The handler itself maps the schema you need without using any instructions in the XML document.
In case the handler does not know where the schema is located, we can indicate where to look for it. This is done using the special "schemaLocation" attribute. Since this attribute belongs to a different namespace, the space must also be specified before using the attribute. For clarity, consider an example.
XML Schema
XML Document
Now let's take a closer look at each line. That's all. Good luck and success in learning XML! The XSD chart is used for traditional cross stitching. The solution developer is HobbyWare. This is a fairly common format for these purposes. The XSD schema replaced the .PAT format, which was also used by PCStitch, causing some confusion. These files contain everything you need for embroidery, in particular, a color legend and a description for subsequent work. The Pattern Maker for cross-stitch program will help you to view materials of this type. XSD is used not only in embroidery. Files with a similar extension determine what attributes and elements can appear in an XML document, and also establish the relationship between its constituent parts. These materials interact with a special language for describing the structure of these files. The purpose of the schema is to define an XSD class that can be used as an alternative to DTD files. Sometimes during operation, various errors may occur. For example, if you see the message "XSD schema validation failed", you are probably trying to associate material with an inappropriate program. Applications that are suitable for working with the format will be discussed later. This application will help to cope with the error of the form "The file does not match the XSD-schema". It's about functional, commercial XML. Serna works with all available stationary systems: Mac OS X, Linux and Windows. The editor has full support for XML catalogs. It is possible to create materials that have a specific structure. XSD schema creation is one of the many features of this application. Inserting elements is greatly facilitated by the fact that the program has contextual lists of attributes and reference information about them. Drag & Drop allows you to drag and drop objects onto the ribbon. An additional check of files at the time of opening has also been implemented. It is possible to work with models and tables. Interaction is carried out even with large and bulky materials. There is an extended navigation through the content. To make it easier to insert different designs, Serna's editor has received a number of specially designed dialogs. The program has a convenient and flexible interface. The open material is displayed in the main window. It is fully presented. There are drop-down lists here. The presence of a content guide is also encouraging. The document is controlled using a special style. Using just a few keys, you can change the profiled open file based on your own requirements and to your liking. A document in Serna can be split and divided into the required number of pages, taking into account the numbering and a certain sequence. This solution is very effective when working with large materials that contain a significant amount of code. At the same time, the standard option for displaying information is convenient if you need to minimize breaks in the document, and this is very important if tables are present. To cope with the error of the form "The file does not match the XSD-schema", and this editor can also open files of the specified type. The solution allows you to interpret documents, as well as highlight elements within the text with color. The content tree view allows the user to view different document nodes. Thus, you can check the correctness of the code, as well as detect errors and warnings. Editing can be done directly from the ZIP archive. If you have an XSD schema in front of you, you can work with it through this application. It is a powerful tool for creating, debugging, and editing documents. There are versions for Windows, Linux and Mac OS. The development of the functions of this solution increases the level of efficiency of work with schemes. The creation of projects of various levels from scratch is available. It is possible to edit existing materials. In this case, several display modes are provided - the final result, hierarchical table, text. The built-in viewer allows you to avoid errors and simplify the use of the program. The application has received a convenient syntax highlighting system. It is possible to comment on the code and set bookmarks. This approach simplifies navigation when working with large projects. There is a built-in converter. You can import databases. There is a tool for comparing two files, which includes a convenient system for displaying the result. This platform is compatible with other similar solutions, which allows you to combine their capabilities. There are several more programs that support working with the type of circuits we are interested in. Among them, Visual Studio deserves special attention. We are talking about the development of Microsoft, which allows you to create various applications. A feature of this platform is a wide range of services available in different programming languages. Services are implemented as middleware that is architecture agnostic. Visual Studio brings together a large number of features that enable development on Windows. The tool has a new environment that makes it much easier to implement applications. You can also work with the format we need through one of the following applications: XML Studio, XML Notepad, JAPISoft EditiX, PSPad editor, Notepad. So we figured out how to fix the error like "Does not match XSD-schema", as well as through which programs to interact with files. Have a problem opening a .XSD file? We collect information about file formats and can explain what XSD files are. Additionally, we recommend the programs that are most suitable for opening or converting such files. File extension .xsd is of the XML Schema Definition (XSD) file type. XML Schema is an international standard with W3C recommendation status, and the XSD file type is a generic designation for XML schema files. XSD is a subset of XML, and its basic concept is similar to the earlier Document Type Definition (DTD) mechanism in that XSD is a metalanguage used to construct and enforce the rules of an arbitrary XML language. File .xsd is a textual listing of the XML source code. It defines an XML Schema, a structured prototype model for ordinary XML documents. XML schema files ( .xsd) can be used to create your own XML-based languages and check (validate) XML documents against rules imposed by a particular XSD schema. XML Schemas ( .xsd) are used by a number of modern XML-enabled software, including web browsers, operating systems, office suites, integrated development environments, etc. In addition, if you have a working knowledge of XML Schema syntax, any file .xsd can be manually opened and edited in a text editor. Without any relation to the above, the extension .xsd also associated with the Pattern Maker Cross Stitch Data File (XSD) file type and format. Pattern Maker is a paid application (Microsoft Windows) for creating detailed cross stitch patterns from digital bitmaps. File .xsd Is a representation of an embroidery pattern created with Pattern Maker. Such XSD files can be opened, viewed, and printed using both Pattern Maker and Pattern Viewer, while editing is only possible with Pattern Maker. Files with the XSD extension often cause confusion among users. This is because there are two types of this format, which represent completely different types of information. Therefore, do not be upset if a familiar application could not open it. Perhaps a different type of file just came across. What are the differences between XSD files and what programs can open them will be discussed later. XML Document Schema ( X ML S chema D efinition) is the most commonly used XSD file type. He has been known since 2001. These files contain a wide variety of information describing XML data - its structure, elements, attributes, and more. There are many ways to open this type of file. For example, let's take the simplest example of this format (purchase order schema) that is offered by Microsoft. XML editors are more suitable software for opening XSD files because they are used to create these types of files. Let's consider some of them in more detail. XML Notepad This program is a version of Microsoft's Notepad that is specifically designed to work with XML files. Accordingly, XSD can be freely opened and edited with its help. Oxygen XML Editor Unlike the previous one, this software product is a much more serious tool for developing XML documents. It presents the structure of the XSD file in the form of a colorful table. XSD files can also be opened using "heavier" software, such as Microsoft Visual Studio, Progress Stylus Studio, and others. But they are all tools for professionals. It makes no sense to install them just to open the file. XSD files can also be opened in any browser. To do this, you can use the context menu or the menu in the same way. "File"(if available in the browser). Or you can simply write the path to the file in the address bar of the browser or drag and drop it into the web explorer window. This is what our sample looks like when opened in Google Chrome: Because of the simplicity of their structure, XSD files can be easily opened by almost any text editor and can be freely modified and saved there. The differences are only in the convenience of viewing and editing. They can be opened directly from a text editor, or from the context menu by selecting the option "To open with". Here are examples of how you can do this with different text editors: Notebook This is the simplest application for working with text files, present by default in any version of Windows. This is how our sample looks like when opened in Notepad: Another unchanged component of Windows, in comparison with the "Notepad" has more advanced functionality. But this is not reflected in the opening of the XSD file, since this editor also does not provide any additional convenience for viewing and editing it. Notepad ++ This program is the same "Notepad", but with a number of additional functions, as evidenced by the pluses in the name. Consequently, an XSD file opened in Notepad ++ looks much more attractive thanks to the syntax highlighting feature. This makes the editing process much more convenient. You can also open XSD files in more complex word processors such as MS Word or LibreOffice. But since these software products are not specifically designed for editing such files, they will be displayed in the same way as in Notepad. Another aspect of the XSD extension is a cross stitch pattern. Accordingly, in this case, the given file format is an image. In addition to the picture itself, these files also contain a color legend and a detailed description for creating embroidery. There is only one way to open such an XSD file. Pattern Maker For Cross Stitch is the main tool for opening embroidery patterns, as it is specially designed for creating and editing them. This is what an XSD file looks like when opened in Pattern Maker. Thus, the XSD file format is basically an XML document schema. If it does not open with text editors, then we have a file containing a cross stitch pattern. When exchanging data between applications, users usually do not think about how this exchange is carried out and what difficulties it may be associated with. The difficulty is that programs can be created on the basis of completely different technologies and, therefore, "speak" in different languages. For applications exchanging information to be able to understand each other, the data must be transmitted in some common language that they understand, which is the extensible markup language. The structure of XML itself must also correspond to a certain format, for which the developers have developed a common set of rules. This set is called the language for describing the structure of an XML document, or simply an XSD schema. Basically, it is a metadata file that stores information about how an XML document should be structured. XSD schemas are used to validate (validate) XML files. The XSD extension also matches the cross stitch pattern, but this is a different XSD format from the one used to describe XML documents. Files of this type contain a pseudo image, a color legend, and an embroidery description. They can be opened only with special applications, while simple text editors are suitable for viewing the contents of XSD files for validating XML documents. Well, we hope that this is an XSD schema you understand, now let's move on to the software used to read files of this type. You can open the XML validation XSD file with any text editor, even Notepad, but it is still more convenient to use the appropriate editors for these purposes. So, let's imagine that we have some kind of XSD schema. What is the best way to open it? Lightweight and convenient text editor, tailored for working with XML files. Displays the contents of an XML and XSD file in two views — a tree structure and a sequence of lines. The first mode is used for editing. XML Notepad supports syntax highlighting, search and replace, regular expressions, and the XInclude function. The main advantage of this program is its simplicity. If you are looking for how to open an XSD file, and at the same time you need a fairly advanced tool, take a look at the EditiX XML Editor program. The application includes an editor and a debugger, and can be used as a full-fledged development environment. The tool supports working with XML, XSD, XSLT, DTD, relational databases, etc., checking XML documents for errors, the program has a built-in XQuery, Grid and CSS editor. Separately, it is worth noting the presence of a schema generator that allows you to view the contents of XML documents in the form of a table of related blocks. An XSD file can be opened by Notepad ++ - a text editor that is suitable for everyone, both novice users and experienced programmers. Notepad ++ supports all basic functions for working with text data, syntax highlighting, advanced searches, regular expressions, code completion, macro recording and much more. The editor is lightweight and, unlike the two previous programs, supports the Russian interface language. Now let's find out how to open the cross stitch XSD file. Even the most advanced code editors are powerless here, and therefore you need a special Pattern Maker program to view the embroidery patterns. The main purpose of this application is to create and edit embroidery patterns, but you can also use it as their viewer. Functionality of Pattern Maker is partially similar to functionality of raster graphic editors, but most of it is represented by highly specialized tools. Okay, now we know what XSD is and how to open it. Understanding the purpose of XSD files can come in handy when parsing a fairly common mistake that users occasionally encounter when working with XML documents. Along with the code, its description indicates that the file or document does not conform to the XSD schema. This effectively means that the XML document being validated contains errors or inconsistencies with the template specified in the XSD file. It doesn't matter which program generated the XML file and why. This can be a report for the tax service or another accounting document, as well as any XML file with a set of some imported data. But the reasons for the discrepancy are different, ranging from the use of an outdated version of the software in which the XML file is created, and ending with the omission of important fields, for example, in the same financial statements.Description
The documents
Syntext Serna
Oxygen XML Editor
Altova XMLSpy
Other solutions
What is the .XSD file format for?
Software to open or convert XSD files
You can open XSD files with the following programs:
Method 1: XML editors
XML Notepad provides many more features than the programs described above. In addition to syntax highlighting, it automatically determines the structure of the document and displays it in a form that is convenient for viewing and editing.
This program is multiplatform both as a stand-alone application and as an Eclipse plug-in.Method 2: Browsers
And this is it, but already in Yandex Browser: 
And here he is already in Opera: 
As you can see, there is no fundamental difference. It should only be noted that browsers are only suitable for viewing files of this type. You cannot edit anything in them.Method 3: Text Editors
Due to the lack of convenience, it will be difficult to edit the XSD file in it, but for a quick acquaintance with its contents, "Notepad" may well be useful.
As you can see, with the exception of the program interface, nothing in the display of the XSD file, compared to Notepad, has changed.
Cross stitch pattern
The program has a rich set of tools. In addition, it can be easily Russified. In addition, it is distributed free of charge.What is the XSD format for?
How to open a file with an XSD schema
Microsoft XML Notepad
EditiX XML Editor
Notepad ++
Pattern maker
