The concept of structured data. Definition and Purpose of a Database
If the pages on your site are marked up in a special way, Google Search their extended descriptions and other useful information may be displayed. For example, a rich description for a restaurant website might include a summary of reviews and pricing information. The data on the page is structured using the schema.org glossary or in formats such as microdata, RDF, microformats, etc. Search Console also provides a Marker tool for this purpose.
In Search Console, on the Structured Data page, you can view relevant information about your site collected by Googlebot. It will also include information about any markup errors that prevent rich snippets or other content from displaying. useful information in search results.
The Structured Data page lists all types of structured data on your site, along with information about whether there are errors in it.
Only objects are indicated top level, found on the pages. For example, if your page contains a schema.org/Event object that contains schema.org/Place data, only the Event property will be taken into account.
If the list is missing structured data that you added to the page using microformats, microdata, or RDFa, use this tool. It allows you to test whether Google can access information on a page and recognize the markup.
Diagnose and resolve markup errors 1. Find out which types of structured data have errorsStatistics for each data type are shown in the table below the graph. For clarity, all types are sorted by the number of errors. Note that the word "element" in this table refers to a single HTML tag in the page's source code. Therefore, if the site, for example, has a data type “Movies” with errors in 3000 elements and a type “Places” with errors in 42 elements, then start working on eliminating errors from movies.
2. Determine the type of errorsClick on a structured data type in the table to see a detailed list of all the problematic elements that apply to it. A list of up to 10,000 URLs will appear, showing the number of errors and their type for each page. Click on the URL to see the detected markup, such as element types and properties.
There are two types of errors in structured data:
- Missing fields
For example, the extended description of an event web page indicates the location and performer, but does not indicate the date of the event. - No minimum or maximum rating
For example, a product is rated on a five-point scale, but the properties bestRating (5) or worstRating (1) are not marked.
Start your investigation with the examples provided in the Structured Data section. Corrective measures depend entirely on how you implemented the markup on the site. For example, if you did this using a content management system (CMS), you will likely need to adjust its settings.
| Parameter name | Meaning |
| Article topic: | Structured Data Types |
| Rubric (thematic category) | Programming |
Data structured type consist of data of other types. Variables of these types can only have one value at a time. Structured data types include:
o Strings;
o Arrays;
o Sets;
o Records;
o Files;
o Classes.
Strings (string types): Represented by three physical types and one general type.
ShortString data is a string, which is actually an array of 256 elements - array. The zero byte of this array indicates the length of the string. Line- ϶ᴛᴏ sequence of code table characters.
Data types AnsiString and Wide String are dynamic arrays, the maximum length of which is actually limited by the size of the computer's main memory. Data of the AnsiString type are encoded in ANSI code, and data of the Wide String type are encoded in Unicode code.
The common type is String, which can be either ShortString or AnsiString, as determined by the $H compiler directive.
Since strings are actually arrays, to access an individual character in a string, you can specify the name of the string variable and the number (position) of this character in square brackets.
String type description format:
Type = string [max string length];
Otherwise: var : string [max string length];
If the maximum allowed line length is not specified, the default length is 255 characters. When used in expressions, the string consists of apostrophes. String data can be used as constants. It is not allowed to use string variables as a selector in a Case statement.
Example: const Addresses = 'ul. Korolenko, 5’;
type Stroka = string;
var Str: Stroka; St1: string; St2, St3: string;
Arrays: array- ϶ᴛᴏ ordered indexed collection elements of the same type having a common name. Elements of arrays can be data of any type, including structural ones. Each element of the array is uniquely identified by the name of the array and an index (the number of this element in the array) or indices if the array is multidimensional. To access an individual element of an array, indicate the name of this array and the element number(s) included in square brackets, for example, arr1 or arr2.
The number of index positions determines the size of the array (one-dimensional, two-dimensional, etc.), while the size of the array is not limited. In mathematics, the analogue of a one-dimensional array is a vector, and a two-dimensional array is a matrix. Array element indexes must be of ordinal type.
There are arrays static and dynamic . Static array is an array, the boundaries of the indices and, accordingly, the dimensions of which are specified when declaring, ᴛ.ᴇ. they are known before the program is compiled. Format for describing a static array type:
Type = Aggau [] of ;
Otherwise: var : Aggau [] of ;
Example.
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type Matrix = a ggау of integer;
Znak = array of char;
Day =(Mon, Tue, Wed, Thu, Fri, Sat, Sun);
var m1, m2: Matrix; a: Znak;
Week: array of Day; r: array of real;
A dynamic array is an array for which only the type of its elements is specified when declared, and the size of the array is determined during program execution. Dynamic array type description format:
Type = Aggay of ;
Setting the size of a dynamic array during program execution is done by the SetLength (var S; NewLength:integer) procedure, which sets a new size equal to NewLength for the dynamic array S. Perform operations with dynamic array and its elements is possible only after setting the dimensions of this array.
After setting the size of a dynamic array, the Length(), Low() and High() functions are used to determine its length, minimum and maximum element numbers, respectively. The numbering of elements of a dynamic array starts from zero, and therefore the Low() function for it always returns the value zero.
Example.
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Var n: integer;
m: array of real;
SetLength(m, 100);
for n:=0 to 99 do m[n]:=n;
SetLength(m, 200);
After describing a dynamic array consisting of real numbers, the size of this array is determined to be 100 elements. Each element is assigned a value equal to its number in the array. Since the numbering of array elements starts from zero, the number of the last one is not 100, but 99. After the loop, the size of the array increases to two hundred.
To describe the type multidimensional dynamic array(for example, two-dimensional) the following construction is used:
Type = Aggau of Aggau of ;
Actions on an array are usually performed element by element, incl. input and output operations. Element-by-element processing of arrays is usually done using loops. The array as a whole (as a single object) can only participate in relational operations and in the assignment operator, and the arrays must be completely identical in structure, that is, have indexes of the same types and elements of the same types.
Sets: A set is a collection of elements selected from a predefined set of values. All elements of a set are of ordinal type; the number of set elements cannot exceed 256. Format, plural type descriptions:
Type = Set of ;
A variable of multiple type can contain from zero to the maximum number of elements of its set. Multiple values are enclosed in square brackets. An empty set is denoted by . The operations allowed on sets are given in the table.
At the same time, there is an in operation (membership check), which determines the membership of the expression ordinal type(first operand) to the set (second operand). The result of the operation will be of type boolean and have the value True if the value belongs to a set.
Entries: z records combine a fixed number of data elements of other types. Individual elements records have names and are called fields. The field name must be unique within the record. Distinguish fixed and variant records . Fixed entry consists of a finite number of fields, its declaration has the following format:
Type = record ;
: ;
: ;
Variant notation, like fixed notation, has final number fields, but provides the ability to interpret the memory areas occupied by the fields differently. All recording options are located in one memory location and allow you to access them by different names. Note that the term “variant record” has nothing in common with the term “variant type”. Variant entry declaration format:
Type = record ;
Case : of ;
: ()
: ();
To refer to a specific field, it is essential to specify the record name and field name, separated by a dot. However, the field name is compound. You can perform the same operations with a field as with a variable of this type.
Example.
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var Man: record;
Man.Name:=’Ivanov M.A.’;
Man .Salary:=5000;
The Man variable is a fixed record that contains the Name, Salary, and Note fields, each field having its own type.
Files: File is a named sequence of elements of the same type placed on external device, most often, on disk. The file has much in common with a one-dimensional dynamic array, but is located not in RAM, but in external memory, and does not require a preliminary indication of the size.
To perform operations with specific file located on disk, the program usually uses the so-called file variable(logical file). A file variable, after its description, is associated with a certain file, so that operations performed on it lead to corresponding changes in this file. After all operations are completed, the connection between the file variable and the file is broken. Now the file variable can be associated with another file of the same type.
Taking into account the dependence on the type of elements, they distinguish text, typed and untyped files . Text file contains strings of variable length characters, typed file constitute elements of the specified type (except file), in untyped file there are elements whose type is not specified. The description of a file variable intended to work with a file must correspond to the type of file elements.
Example.
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var f1: TextFile;
f2: File of integer;
f3: File of real;
here the f1 variable is intended to work with text files, the f2 and f3 variables are for typed files containing integer and real numbers, respectively, and the f4 variable is for untyped files.
Structured data types - concept and types. Classification and features of the category "Structured data types" 2017, 2018.
Simple data types: variables and constants.
Programming languages.
Lecture 4.
The real data that the program processes are numbers (integers and reals), symbols, and logical values. These data types are called basic. All data processed by a computer is stored in memory cells, each of which has its own address. In order not to keep track of which address the data will be written to, programming languages use the concept variable, which allows you to escape from the address of a memory cell and communicate with it using the name ( identifier).
Variable– there is a named object (memory cell) that can change its value. Name variable indicates meaning, and the method of its storage and address remain hidden from the programmer. In addition to its name and value, a variable has type, which determines what information is in memory.
The variable type specifies:
The method used for recording information into memory cells;
The required amount of memory to store it.
If variables are present in a program throughout the entire duration of its operation, they are called static. Variables that are created and destroyed at different stages of program execution are called dynamic.
All other data in the program, the values of which do not change throughout its operation, are called constants or permanent. Constants, like variables, have a type.
To improve productivity and quality of work, it is necessary to have data that is as close as possible to real analogues. A data type that allows several variables to be stored together under one name is called structured. Every programming language has its own structured types. One of the structures that combines elements of the same data type is array.
Array is an ordered collection of quantities of the same type that have a common name, the elements of which are addressed (distinguished) by serial numbers (indices).
Elements of an array in computer memory are stored nearby; single elements of a simple type do not imply such an arrangement of data in memory. Arrays differ in the number of indices that define their elements.
A one-dimensional array assumes that each element has only one index. Examples of one-dimensional arrays are arithmetic and geometric sequences that define finite series of numbers. The number of elements in an array is called dimension. When defining a one-dimensional array, its dimension is written in parentheses next to its name. For example, an array consisting of elements a1, a2... a10 is written as A(10). The elements of a one-dimensional array are entered element-by-element, in the order necessary to solve specific task. The process of entering array elements can be depicted in the form of a flowchart as follows:
For example, consider the algorithm for calculating the arithmetic mean of positive elements of the numerical array A(10). The algorithm for solving the problem will contain the calculation of the sum (denoted by S), including the positive elements of the array (ai>0), and the number (denoted by N) of its terms.
Recording the algorithm in pseudocode:
1.Repeat 10 times (for i=1,10,1)
1.1.Input ai.
2.Initial value of the sum: S=0.
3.Initial counter value: N=0.
4.Repeat 10 times (for i=1,10,1):
4.1.If ai>0, then S=S+ai and N=N+1.
5.If N>0, then calculating the arithmetic mean SA=S/N; output SA. Otherwise: output “There are no positive elements in the array.”
Recording the algorithm in the form of a block diagram:
A two-dimensional array assumes that each element has two indices. In mathematics two-dimensional array(or table of numbers) is called a matrix. Each element has two indices aij, the first index i determines the row number in which the element is located (horizontal coordinate), and the second j – the column number (vertical coordinate). A two-dimensional array is characterized by two dimensions N and M, which determine the number of rows and columns, respectively.
The elements of a two-dimensional array are entered line by line, in turn, each line is entered element by element, thereby defining a cyclic construction that implements the nesting of cycles. Block diagram of the algorithm for entering a two-dimensional array:
The outer loop determines the number of the input line (i), the inner loop determines the number of the element in the column (j).
26.05.2017 Reading time: 30 minutes
One of the deepest desires of website owners and SEO specialists is to make their website stand out in search results so that it stands out from competitors and users click on it more often. Most effective method achieving this goal is working with structured data. In this article we will try to understand what structured data is and how you can implement it on your website.
Where did it all start?The unified scheme of formats for semantic site markup, which we now all know and use, appeared in 2011 with the support of such giants as Google, Yahoo! and Microsoft (later a fourth player, Yandex, joined). Previously, data markup existed in different formats and there was no unified structure. For example, Yahoo! there was a service called “SearchMonkey”, which already in 2008 made it possible to mark up data on a page and generate unique snippets in search results your search engine.
Corporations had a global goal - to develop a common format for structured data that would improve the display of sites in search engines and improve the quality of search. The initiators achieved their goals, as a result of which the schema.org dictionary was born, which combines great amount rules for microdata markup on the site.
What is structured data?Structured data is information that is presented in a unified and correct form in compliance with a certain set of rules.
We will not describe the principles of working with each dictionary; we will analyze in more detail only three of them: Json-ld, Opne Graph and schema.org.
Let's start with the popular microdata dictionary schema.org. The result of the collaboration between Google, Yahoo!, Microsoft and Yandex is actively developing and is regularly updated to this day. At the time of creation of the article, the dictionary contains descriptions for 589 document types, 860 object properties and 114 specific meanings. A complete list of all properties is listed in a branched hierarchy on this page.
The main highest entity type in the schema.org dictionary is Thing, which in turn is divided into several other subtypes. Some of them:
- CreativeWork is a general set of rules for describing creative activities: articles, books, films, photographs, software, etc.;
- Event – a set of rules for events that have occurred or will occur in certain period time: meetings, concerts, exhibitions, etc.;
- Intangible is a service class that includes several intangible things such as sizes, ratings, descriptions of job vacancies, services, etc.;
- Organization – a set of rules for marking organizations, full list different types of businesses are listed on the localBusiness page. You can also view this list in Yandex help https://yandex.ru/support/webmaster/supported-schemas/address-organization.html;
- Person – an entity used to describe living, deceased, fictional individuals or characters;
- Place – a set of rules for something that has a fixed physical location (building, park, monument, etc.);
- Product is everything that is created for sale. For example, a pair of shoes, a ticket or a car.
Each subtype includes a large number of tags for description, so almost any type of business will find the necessary type of markup.
Most tags in the dictionary have use cases in the form of an example piece of HTML code or a JSON-LD script. Below we will look at examples of page layouts with an article (article), product (product) and organization (organization).
Article markup template using schema.orgMost often, microdata such as URL, datePublished, dateModified, headline, image, author, publisher, etc. are marked. Let’s look at specific example:
Examples of article markup using schema.org FIRST NAME LAST NAME
"LOGO WIDTH IN PIXELS" height= "LOGO HEIGHT IN PIXELS" src= "LOGO IMAGE LINK" alt= /> ARTICLE TITLE ARTICLE DESCRIPTION AUTHOR NAME HEADLINE H1
"PREVIEW WIDTH IN PIXELS" height= "PREVIEW HEIGHT IN PIXELS" src= "LINK TO PREVIEW IMAGE" alt= "ALTERNATE PREVIEW DESCRIPTION"
/>
ОСНОВНОЙ ТЕКСТ СТАТЬИ ДОЛЖЕН БЫТЬ ЗДЕСЬ
!}
Most tagged articles follow a similar pattern. It is worth noting that in in this example Some tags are indicated in the section (meta description and link to the author in g+), and the rest is written in the body of the HTML document. It is not necessary to use some tags, for example, an article will feel great without marking it with the articleBody or publisher tags, but then it is unlikely will be tested for validity in Yandex or Google tools.
Image 3. Example of a page in search results with article micro markup in Google. The publication date appears next to the article.
Image 4. An example of a page in search results for the same request as in Image 3, only in Yandex. The date appears on the right, with the date published or created at the top and the date modified below.
Product card micro-markup template using schema.orgThe next type of micro markup that we will consider will be product or, in other words, the semantic markup of a product card.
CONTENTS H1
"LINK TO IMAGE" title= "CONTENTS H1"
>!} PRICE IN RUBLES INDICATING PRODUCT AVAILABILITY PRODUCT DESCRIPTION
Pay special attention to the price format, since most of the errors in the micro-marking of product cards lie there. We can write any price in text in any format, and directly in the price tag itself we indicate the price strictly in monetary format, otherwise search engines will ignore this line.
Image 5. Example from Google results indicating the price in the “FROM” and “TO” format.
Organization schema template using schema.orgThe last pattern we'll look at is the organization markup. Typically, this markup is used to structure information on a contact page.
NAME OF ORGANIZATION STREET, CITY, REGION. "LINK TO LOGO" /> Phone: PHONE NUMBER
schema.org has a very large vocabulary. Because of this, difficulties may arise when working with it, but not all tags in the markup are required and most can be abandoned. In the examples given, I have indicated the most basic tags that can be used when working with schema.org markup, but there can be much more.
Google has a special tool for marking up pages according to the schema.org dictionary. It makes creating page layouts much easier.
Image 6. Example from Yandex. Additional Information about the organization is displayed under the page description and can be implemented either manually, using markup, or using the Yandex.Directory service.
Pros and cons of schema.org micro markup- Large dictionary that is constantly updated;
- Supported by all popular search engines;
- The code is not hidden by scripts and is entirely contained in the page content;
- Improves the display of snippets in search results;
- You can find markup for almost every site;
- There are plugins to automate the generation of micro markup;
- Actively developing and expanding.
- A large number of markup schemes can scare off an unprepared user;
- Needed basic knowledge layout and code changes of pages;
- Complicates the HTML code, which slows down site development;
- All official reference documentation is in English;
- Not all properties have examples of use on the official website.
When working with schema.org micro markup, services such as:
- Structured Data Validation Tool from Google;
- Assistant on micro-markup of pages according to the schema.org dictionary from Google. As a result, we get the HTML code of the page with already implemented micro markup;
- Checking semantic markup from Yandex;
- Official markup website;
- Unofficial translation of the schema.org website into Russian;
- “All In One Schema.org Rich Snippets”, “Wprichsnippets.com”, “Schema App Structured Data” - plugins for WordPress that form semantic markup schema.org automatically;
- Notepad++ - or any other text editor.
This protocol was developed by Facebook to improve the display of link snippets from external sites on social networks. This is probably one of the simplest and smallest microdata dictionaries. You can start implementing markup with four basic properties:
- og:title - page title.
- og:type - object type, for example, “music.album”(album). Depending on the type, other properties are supported. All possible characteristics of the type tag are listed on the official website.
- og:image - URL of the image.
- og:url - the object's canonical URL.
All “Open Graph” markup tags are written in the container.
In addition to the main properties, you can also specify additional ones that will improve the display of links on social networks:
- og:audio – URL to the audio file if music is played when opening the page.
- og:determiner is the word that appears before the name of this object in a sentence. Type enum (a, an, the, "", auto). If auto is selected, the data consumer must choose between "a" or "an". The default is " " (empty). The tag is most relevant for the English-speaking segment due to the use of various articles like “a”, “the”, “an”, etc.
- og:description – page description, allowed number of characters from 160 to 295 characters.
- og:locale – language and country. The display format is language_TERRITORY, the default is en_US. For Russian-speaking segment the tag ru_RU is written.
- og:locale:alternate – alternative language or country.
- og:site_name – site name.
- og:video – video URL.
Below is an example of HTML code with all possible properties; in practice, some of the specified tags are not specified and the standard four properties are enough:
PAGE TITLE...
The last type of markup and data structuring that we will look at is JSON-LD. This terrible name stands for “JavaScript Object Notation Linked Data”. The Consortium is responsible for developing the format World Wide Web" or in other words, "W3C". This format performs the same function as schema.org, but in a slightly different way: it structures data using JavaScript, which makes the work several times easier.
One of the advantages of this format is that the schema.org dictionary is used to describe the data. Thus, using JSON-LD scripts we can describe any type of entity and improve the display of our site in search results, spending a minimum amount of time on this. Moreover, this can be done without introducing HTML tags into the body of the page; you just need to specify in the container, and then write everything the necessary conditions markup and close the script.
For clarity, let’s compare the schema.org and JSON-LD markup:
Sneakers
Sneakers ( "@context" : "https://schema.org/" , "@type" : "Product" , "price" : "100.00" ) Sneakers
Article markup template using JSON-LDI took an example of markup using JSON-LD based on the micro markup of an article in schema.org from the same material above. All the same properties are used.
ARTICLE TITLE //The script type is indicated, in our case it is ld+json ( "@context" : "https://schema.org" ,//The library that will be used to mark up the page is specified "@type" : "Article" ,/ /Specify the entity type "mainEntityOfPage" : ( //The ID of the article is specified, usually the link to the article is simply specified "@type" : "WebPage" , "@id" : "LINK TO ARTICLE" ), "url" : "LINK TO ARTICLE " , // Specify the canonical link to the article "datePublished" : "DATE OF PUBLICATION" , // Specify the date of publication "dateModified" : "DATE OF CHANGE" , // Specify the date of modification "headline" : "HEADING H1" , // Specify the title "image" : ( "@type" : "ImageObject" , "url" : "LINK TO PREVIEW" , //Inserts a link to the image for the article preview "height" : PREVIEW HEIGHT IN PIXELS , //Specifies the height and width of the image in pixels "width" : PREVIEW WIDTH IN PIXELS), "articleBody" : "" , "author" : ( "@type" : "Person" , "name" : "AUTHOR NAME" , //Specify the author's name "url" : "LINK TO AUTHOR'S PROFILE (G+, PERSONAL PAGE ON THE SITE)" //A link to the author's profile is written in Google Plus or at personal page on the site), "publisher" : ( "@type" : "Organization", "name" : "ORGANIZATION NAME", // Specify the name of the organization "logo" : ( "@type" : "ImageObject" , "url" : "LINK TO LOGO" ,//Indicates a link to the company logo "height" : LOGO HEIGHT , //Specifies the height and width of the logo "width" : LOGO WIDTH ) ) ) ARTICLE TITLE
Arises logical question: which is better schema.org or JSON-LD? It is impossible to give a definite answer here. Working with micro-markup in JSON-LD format is easier and more pleasant than working with the same schema.org dictionary in HTML format, but it also has its drawbacks. For example, the Google search engine is advised to use this technology to mark up its pages. But there are problems with Yandex: this type of markup is not yet displayed in search results due to scripts, although pages with JSON-LD markup are checked for validity.
The Yandex search engine does not display information marked up using the JSON-LD meta-language in search results.
Image 8. Letter from Yandex technical support regarding plans for JSON-LD. Thanks to the user for the screenshotOleh Holovkin .
IN in this case you need to set your priorities correctly. If you need extended snippets in Yandex and Google, then we use the good old schema.org markup; if we focus on the West and our main search system only Google, then the JSON-LD markup needs to be taken and implemented without delay.
Pros and cons of JSON-LD markup- The format is somewhat simpler compared to schema.org;
- Recommended by Google;
- For WordPress engine there are high-quality plugins for work;
- Thanks to JavaScript, the markup is “invisible” to the average user, unlike HTML;
- The script is placed only in the container without introducing additional lines of code into the body of the site;
- Validated in official instruments Yandex and Google checks.
Those marking methods listed above refer to direct intervention in source pages, but there are other methods of structuring data. These are Data Highlighter (Marker) from Google and “Products and Prices” from Yandex. Using these tools, you can directly expand page snippets in search results from the webmaster panel.
Image 9. “Marker” in Search Console and the “Products and Prices” service from Yandex.
Google markerIn order to start marking, you need:
- Events
- Local organizations
- Book Reviews
- Applications
- Products
- Restaurants
- Articles
- TV serials
- Movies
Image 10. Panel for selecting the type of information for markup in Search Console.
Image 12. Button for deleting an incorrectly defined markup page in Search Console.
Image 13. Example of a list of already marked up pages using Google Marker.
This concludes markup using Google Marker. In this case, you absolutely do not need to know HTML or JavaScript; you just need to manually mark up each page, and Google itself will process the data and make adjustments to the search snippets. But Marker also has its pros and cons.
Pros and cons of markup using Google Marker- Markup without interfering with the source code of pages;
- The tool is located directly in Google Search Console;
- Pages are marked semi-automatically;
- You can group pages by type;
- The markup will only appear in Google search results;
- The tool does not always mark up information correctly;
- When marking a large website, there is a lot of manual work.
This tool itself does not quite relate to the usual understanding of page markup, since in Yandex it is usually used to load information about a product into Yandex.Market in YML format. Oddly enough, Yasha was able to find a use this species information about the product, and now in organic search results you often find sites marked with this service. main feature“Products and prices” is the display in Yandex search results of the price of a product/service to the right of the link to the site.
Image 14. An example of displaying the price of a service in Yandex search results with the “Products and Prices” service connected.
The “Products and Prices” service can be used not only by online stores, but also by organizations that provide services. In this case, you will have to create the YML document manually.
So, in order to connect the “Products and Prices” service in Yandex, you need to:
Image 15. Yandex offersfamiliarize with YML format andmanagement by connection.
Pros and cons of the Yandex Products and Prices tool - It greatly distinguishes the site from other competitors in search and increases CTR;
- Before going to the site, the user receives information about the cost of the service/product;
- In addition to the price, the YML document specifies other parameters that are also taken into account when generating the snippet;
- In most popular website engines, file generation occurs automatically or semi-automatically.
- Results with prices will be visible only in Yandex results;
- Uploading a YML document is not provided in all CMS;
- If prices on the site change frequently, regular document generation is required;
- Labor-intensive if you need to mark up a large number of pages manually.
Unlike Google Marker, to work with a YML file you will need the following tools to work:
- List of website engines with the ability to upload YML documents;
- YML document generator for manually generating a file;
Implementing structured data markup is important step, which can subsequently increase the site’s CTR in search and improve the display of content in search results. There are several ways to mark up your website, but at the moment the most proven is the implementation of schema.org markup, since other methods either have limited functionality or are marked within the same search engine.
Each method of data markup has its own advantages and disadvantages; before starting implementation, you should soberly assess your capabilities and choose best option. Individual markup methods can be combined with each other, for example, Open Graph with schema.org and “Products and Prices” from Yandex. And remember: the presence of micro markup on the site does not guarantee a change in the search snippet in the results; first of all, it makes it easier for search engines to crawl the site.
Article prepared by: Abdullin Konstantin, Technologist SEO-expert of the website company
Topic 4.7
Algorithm programming
formation and processing
one-dimensional arrays
Structured Data
Often it is necessary to process not single data, but a collection of data of the same type. For example, task tabulating function, which consists of obtaining a sequence of values given function for several argument values. To intermediately store each value of the received data, you need to declare your own variable with a unique name.
Referring to each sequence variable by name turns into a long string of similar operations with each variable. The program code becomes poorly visible. Such a program requires a lot of memory to accommodate.
To resolve these problems in algorithmic languages structured data is used. The simplest structured data is data sets .
An array is a collection of variables of the same type ( array elements). All variables have the same name, and to access a specific element of the array, an additional identifier is used - its serial number(index), which starts from 0.
In addition to arrays in programming, other standard data structures can be used to build effective algorithms, such data structures as stacks, queues, related lists and others.
Along with standard data structures, user-defined data structures can be used. These data structures are defined by object-oriented programming tools using classes .
4.7.2. Tools for describing and working with one-dimensional
data sets
Array – sequence of variables same type, united by common name. For example: a one-dimensional array a(9) consists of 10 elements with a common name a: a(0), a(1), a(2), a(3),..., a(9), ordered by index i , which takes values from 0 to 9:
| a(i) | ||||||||||
| i |
An array is declared in a VB program in the same way as simple variables are declared. If the array is declared local, it can only be used in the procedure in which it is declared. If the array is declared as global, it can be used anywhere in the program.
When declaring an array, the declaration statement must include the following information:
· array name– name (identifier) that is used to represent the array in the program;
· data type– the data type that the array elements have;
· dimension (rank)– the number of dimensions of the declared array (i.e. the number of indexes when declared; one-dimensional arrays have one dimension);
· amount of elements– the number of elements that will be contained in the array.
Let's look at examples of some array descriptions:
In these examples the following arrays are declared:
· one-dimensional array d, consisting of 31 elements of type Integer with indices from 0 to 30;
· one-dimensional array a, consisting of 11 elements of type Double with indices from 0 to 10;
· two-dimensional array b, consisting of 14x11=151 elements of Single type with indexes along rows from 0 to 13 and columns from 0 to 10.
Please note that the value of the lower bound of the array in VBthere can only be 0 .
Thus, the array consists of elements that can be accessed using indexes. When accessing array elements indices are written after the name in parentheses and can be any valid integer expression. For example, d(24), a(2*i+1).
Note that the number of indices indicates the size of the array. So, in the above example, the dimension of the array a(10) is equal to one. The array b(2,3) has dimension 2.
Unlike dimensions , array size is the number of elements in the array. In our example, the size of the array, a(10) is 11.
Before using an array in a program, it must be declared using the Dim statement, and the elements of the array must be assigned specific values. Dim operator allocates memory space computer to place array elements, zeros elements of numeric arrays or fills elements of string arrays empty lines ("""").
As for simple types, data, when declaring arrays that are structured types data, there are two ways to allocate memory: static– at the compilation stage before executing the program, and dynamic– during program execution. By default, an array whose boundaries are specified by constant expressions is considered static. Memory to accommodate such an array is allocated at the compilation stage and is retained for the entire execution period.
You can fill array elements with specific values using input array element values using the operator assignments or using initialization array elements.
Initializing array elements is an element-by-element assignment of a value in an array declaration statement. In this case, the size of the array is not specified in parentheses after the array name, but is determined implicitly by the size of the list of values. The list of values starts with the element at index 0 and is enclosed in curly brackets, For example:
It should be noted that, regardless of the specific task, array formation and processing algorithms are usually built using regular cyclic structures:
To make it easier to work with arrays in procedures, the built-in function is used to determine the upper bound of the array
Bound( ArrayName).
This function returns (determines) the number last element array and allows you to process arrays in procedures without passing the number of array elements as a parameter. For example,
You can also use the GetUpperBound() method to determine the upper bound of a one-dimensional array. Since the array is one-dimensional, the value 0 should be specified in parentheses. For example:
In addition, we know that the ByVal keyword specifies that an array argument is passed by value, and the ByRef keyword specifies that an array argument is passed by reference. Note that if the ByVal or ByRef keywords are omitted, the array argument is passed by reference.
Thus, when describing the formal parameters of any procedure after ArrayNameYou must always include empty parentheses because they indicate that this parameter is a one-dimensional array.
Note that there are no parentheses after the array name, which is the actual parameter.
As you know, passing arguments by value (using keyword ByVal) causes VB to pass a copy of the data to the procedure. Therefore, you should not pass arrays by value unless you really need to.