5 обязательных книг по SQL 1⃣ “SQL: быстрое погружение”. Автор - Уолтер Шилдс Эта книга поожет вам разобраться как в основах SQL, так и в расширенных возможностях этого языка. Читатели, уже имеющие опыт работы с SQL, могут пользоваться книгой Шилдса как справочником. 🔴 Скачать 2⃣ “MySQL Cookbook”. Авторы - Света Смирнова, Алкин Тезуйсал Книга пригодится всем, кто работает с MySQL как в личных проектах, так и на…

Channel
SQL Pro
@sqlprofi
On this record: Growth · Engagement · What this channel posts · Reactions · Posts · Polls · Citations · Cite this entry
4,948subscribers
-5 since we began measuring on 7 August 2026
Risers and fallers across the register · movement among entries of 3,162–10,000.
Register entry
| Telegram ID | -1001301676145 |
|---|---|
| Type | Channel |
| Username | @sqlprofi |
| Description | SQL Pro - всё об SQL Реклама: @anothertechrock Контент канала: 1. Разбор вопросов с собеседований 2. Трюки SQL 3. Видео 4. Тесты 5. Задачи на логику 6. Юмор |
| Created | Between 1 March 2018 and 30 June 2021— estimated from Telegram’s id allocation, not measured. How this range is calculated. |
| First recorded | 7 August 2026 |
| Last confirmed live | 10 August 2026 |
| Measurements held | 3 |
| Confirmed unchanged | 1 time, most recently 10 August 2026 |
| On Telegram | t.me/sqlprofi |
Growth
| Measured (UTC) | Subscribers | Change |
|---|---|---|
| 10 Aug 2026, 11:01 | 4,948 | -5 |
| 7 Aug 2026, 05:00 | 4,953 | no change |
| 7 Aug 2026, 04:51 | 4,953 | first reading |
Engagement
20 posts held, back to 20 March 2026 — the reader has not yet reached the start of this channel’s public history, so older posts may sit further back, unread. Read across 8 pagesof Telegram’s post history, 20 posts per page.
- ERR · 30 days
- 11.1%
- avg views ÷ 4,948 subscribers
- Avg views / post
- 548
- 4 posts measured
- Reaction rate
- 0.415%
- reactions ÷ views · ER floor
- Posts in window
- 4
- of 20 held
ERR is average views per post over the last 30 days divided by subscribers, the definition TGStat uses, so this figure is comparable with the one you will see elsewhere. It falls structurally as a channel grows: a high ERR on a small channel and a low one on a large channel describe reach mathematics, not quality. We publish the figure and the sample it came from and pass no verdict on it.
ER is defined industry-wide as (forwards + reactions + comments) ÷ views— note the denominator is views, not subscribers. Telegram’s public web preview carries views and reactions but not forward or comment counts, so the reaction rate above is the reactions term only and is therefore a floor: the true ER for this channel is higher by an amount we have not measured and will not estimate. It is computed over the 3 of 4 measured posts that carry a reaction reading, and over those same posts' views.
| Window | Rolling 30 days · latest post in window 10 August 2026 |
|---|---|
| Posts held | 20 (20 March 2026 – 10 August 2026) |
| Views total | 2,193 |
| Reactions total | 8 |
| Forwards / comments | not exposed by the public surface — not measured, not estimated |
| Readings taken | 12 Aug 2026, 05:03 UTC |
Views are a single reading per post, taken at the time above. A post published in the last day or two is still accumulating views, which pulls the 30-day average down slightly. That is a property of the standard definition rather than a fault in it, so we keep the definition rather than “correcting” the number into something nobody can reproduce.
Precision. Telegram publishes view counts on its public widget in short form — 8.12K, 3.7M — so any reading at or above 1,000 reaches us rounded to three significant figures, and only counts below 1,000 are exact. Averages and rates derived from them are shown to the same precision rather than to the unit: a figure like 3,701,250 would assert digits nobody measured.
Reaction counts are published per emoji and rounded the same way, so a total below 1,000 is exact and a larger one is a sum that may carry a rounded component from each emoji above 1,000. Because it is a sum, it does not look rounded — read a large reaction total as three significant figures per contributing emoji rather than as the figure it prints.
What this channel posts
- Photos
- 99
- Links
- 77
Lifetime counters from Telegram’s own channel header, read 12 August 2026 — not the date at the top of this page, which is when the subscriber count was last read. Below Telegram’s rounding threshold, so these counts are exact.
Reaction mix
36 reactions across 10 posts, in 12 distinct kinds. The most used accounts for 33.3% of them.
| Reaction | Count | Share | Share, drawn |
|---|---|---|---|
| 👍 | 12 | 33.3% | |
| ❤ | 6 | 16.7% | |
| 🔥 | 5 | 13.9% | |
| 🙏 | 3 | 8.33% | |
| 😁 | 2 | 5.56% | |
| 🤡 | 2 | 5.56% | |
| 💩 | 1 | 2.78% | |
| 😱 | 1 | 2.78% | |
| 🤔 | 1 | 2.78% | |
| 🤝 | 1 | 2.78% | |
| 🤯 | 1 | 2.78% | |
| 🥴 | 1 | 2.78% |
No sentiment is inferred, and none should be read in. This table is ordered by count and by nothing else. Emoji do not carry stable meaning across languages or communities — 🙏 is thanks in one channel and mourning in another — so we publish which ones were pressed and how often, and pass no judgement on what an audience meant by them.
Precision. Telegram publishes reaction counts per emoji and short-forms each one — 4.34K, 1.2M — so any single kind at or above 1,000 reaches us at three significant figures, and only counts below 1,000 are exact. The shares above are ratios of those figures and carry the same error. This is also why the total here can differ slightly from a reaction total printed elsewhere on the page: both are sums of the same rounded parts, taken over samples with different edges.
Coverage. Reactions were read on 14 of the 20 sampled posts in this sample. Summed by Telegram’s own count on each post — not by adding up the per-emoji breakdown above — those same posts carry 36reactions in total: the kind of figure the paragraph above means by “a reaction total printed elsewhere on the page”.
Measured over the 20 most recent posts we hold, published 20 March 2026 to 10 August 2026, using the newest reading held for each. Telegram Stars are excluded: they are a payment, not a reaction, and they have their own section.
Recent posts
Трюк дня. Сравнение с предыдущим. Решение. Решение: использование DATEDIFF DATEDIFF: эта функция вычисляет разницу между двумя датами. Она используется для того, чтобы обеспечить сравнение именно «сегодняшних» и «вчерашних» температур. Если сформулировать обычным языком следующий запрос, то окажется, что он выражает следующую идею: нужно выбрать такие идентификаторы, чтобы температура, соответствующая представляем…
Трюк дня. Сравнение с предыдущим Напишите SQL-запрос, который находит в таблице weather все даты (идентификаторы дат), когда температура была бы выше температуры на предшествующие им даты. То есть, нас интересуют даты, в которые «сегодняшняя» температура выше «вчерашней». Решение будет вечером. #tips
👍2🤡2
Трюк дня. Извлечение имени, отчества и фамилии из строки с полным именем. Решение. SELECT SUBSTRING_INDEX (SUBSTRING_INDEX (fullname, ' ', 1), ' ', -1) AS name, IF (LENGTH (fullname) - LENGTH (REPLACE (fullname, ' ', '')) > 1, SUBSTRING_INDEX(SUBSTRING_INDEX (fullname, ' ', 2), ' ', -1), NULL) AS middlename, SUBSTRING_INDEX (SUBSTRING_INDEX (fullname, ' ', 3), ' ', -1) AS surname FROM customers; #…
👍3🤔1
Решение сегодняшней задачи на логику и мышление. Вместо знака вопроса должно стоять число 179. Если двигаться по часовой стрелке начиная с 3, то каждое последующее число равно удвоенному предыдущему, к которому прибавили 1, 3, 5, 7, 9. 3 × 2 + 1 = 7. 7 × 2 + 3 = 17. 17 × 2 + 5 = 39. 39 × 2 + 7 = 85. 85 × 2 + 9 = 179. #логика
👍4🔥2🤝1
🔥 Для начинающих аналитиков и разработчиков. Освойте главный инструмент для работы с данными. Курс проведет вас от первых SELECT до оконных функций и сложных соединений. Формат: 15 коротких уроков + PDF-шпаргалка. Доступ навсегда. 💰 Цена: 6 900 ₽. 🆓 Попробуйте бесплатно: на странице курса есть тариф с вводным уроком и конспектом на 2 дня. 👉 Узнать подробнее и записаться: https://high.skillspace.ru/course/125816/…
🔥3👍2🤯1😁1😱1
Задача на мышление и логику. Определите, какое число должно стоять на месте знака вопроса. Решение будет вечером. #логика
❤1
Решение сегодняшней задачи на логику и мышление. Минимальное количество взвешиваний – 3, ведь даже если мы взвесим 2 раза, то как мы узнаем, какая из монет фальшивая? Большую часть монет составляют настоящие, так что 2 монеты с одинаковым весом и будут настоящими, третья с другим весом – фальшивой. Ответ: 3 взвешивания. #логика
Задача на мышление и логику. Дано 12 монет, из которых 11 – настоящие, и только 1 – фальшивая. Фальшивая монета отличается от настоящих по массе. Какое минимальное количество взвешиваний необходимо, чтобы обнаружить фальшивую монету? Для взвешивания используются чашечные весы. Решение будет вечером. #логика
Трюк дня. Извлечение имени, отчества и фамилии из строки с полным именем. Решение. SELECT SUBSTRING_INDEX (SUBSTRING_INDEX (fullname, ' ', 1), ' ', -1) AS name, IF (LENGTH (fullname) - LENGTH (REPLACE (fullname, ' ', '')) > 1, SUBSTRING_INDEX(SUBSTRING_INDEX (fullname, ' ', 2), ' ', -1), NULL) AS middlename, SUBSTRING_INDEX (SUBSTRING_INDEX (fullname, ' ', 3), ' ', -1) AS surname FROM customers; #…
🥴1
Трюк дня. Извлечение имени, отчества и фамилии из строки с полным именем В столбце fullname таблицы customers содержится имя, отчество и фамилия в следующем формате: 'name middlename surname'. Напишите MySQL-запрос, который извлечет name, middlename и surname в отдельные столбцы. Если middlename не существует, то в результате в middlename должен быть NULL. Например, из 'Alena Igorevna Petrova' должны получиться 3…
❤3💩1
🔥24 июня в 20.00 мск. приглашаем на открытый урок: "Отказоустойчивый и высоко-доступный кластер RabbitMQ" На вебинаре разберём практические подходы к созданию отказоустойчивой и высоко-доступной очереди сообщений для высоконагруженных систем. 📌 Что будет: — Запуск и настройка кластера: Quorum Queues и Mirrored Queues (синхронная репликация) — Синхронизация очередей и обеспечение согласованности — Dead Letter Queue …
❤1👍1
Showing the 12 most recent of 20 posts we hold for @sqlprofi. View and reaction counts are the latest single reading for each post, not a live figure, and a recent post is still accumulating both. A view count marked ≈ was rounded by Telegram before we ever saw it — t.me prints views in full below 1,000 and to three significant figures above, so ≈1,200,000 means somewhere between 1,150,000 and 1,249,999. Unmarked counts are exact. Text is reproduced from the public post preview and truncated for length.
Polls
The 3 polls we hold for this entry, as Telegram rendered them when we read the post. A poll’s figures keep moving after that, so each one is dated.
Отличаются ли в SQL операторы AND и & (амперсанд)?
- Между ними нет различий16%
- Оператор & не поддерживается стандартом SQL54%
- Приоритет AND ниже, чем приоритет &9%
- Приоритет AND выше, чем приоритет &7%
- Узнать ответ14%
Shares as published. No per-option vote count is published by Telegram, so none is shown.
Выберите корректный пример использования функции CONCAT:
- SELECT CONCAT = index AND city FROM Orders;1%
- SELECT CONCAT IN (`index`, `city`) FROM Orders;8%
- SELECT CONCAT(`index`, " ", `city`) FROM Orders;74%
- Нет правильного примера10%
- Узнать ответ7%
Shares as published. No per-option vote count is published by Telegram, so none is shown.
Каков будет результат выполнения следующего запроса: SELECT AVG(Age) FROM Persons
- 15016%
- 10040%
- 7520%
- UNKNOWN, поскольку присутствует NULL9%
- Запрос не выполнится (завершится ошибкой), поскольку присутствует NULL15%
Shares as published. No per-option vote count is published by Telegram, so none is shown.
Percentages only — there are no per-option vote counts here, because Telegram publishes none.The public post preview gives each option’s share and a single voter total, and nothing else. Multiplying one by the other would produce a per-option tally that looks measured and is not: the shares are rounded to whole numbers before we ever see them. We print what was published and leave the column that does not exist empty.
The shares need not add up to 100.Rounding alone puts many polls at 99 or 101. A poll that allows more than one answer per voter runs well past 100 by design, and several here do. The bars are drawn against a fixed 100% track at each option’s own percentage rather than normalised to the total, so a poll that exceeds it shows that it does instead of being quietly rescaled.
Read from the 20 most recent posts we hold, published 20 March 2026 to 10 August 2026. Telegram labels each poll by kind — an anonymous poll, a quiz, a closed set of final results — and that label is reproduced rather than paraphrased.
Citation-graph rank
Citation-graph rank — 1,147,947 of 1,160,990entries in the measured graph. A weighted position computed from the forward and mention edges below — republished posts weigh more than named mentions — and recomputed periodically, over the whole graph. Published only as this ordinal position, never as a score: a position is a fact, and a score printed beside one channel’s name would read as a verdict this register does not make. The two counts beneath stay separate for the same reason mentions are never summed with forwards anywhere else on this page — a named-by count costs nothing to manufacture. The top 100 by this measure, or how it is computed.
Mentions
Named by 1 registered channel — every channel on the register whose own posts have named this one, by its current username or any other username it currently holds, merged from two separately captured readings of the same fact so a namer caught by only one of them is not missed and a namer both caught is not counted twice. A username this channel has since dropped is not matched — that handle may belong to someone else now, and crediting today’s namer to yesterday’s owner would misattribute it.
Named by
Channels on the register whose posts name this channel's handle.
Names
Channels on the register whose handles appear in this channel's posts.
A mention is a weaker signal than a forward and is counted separately for that reason — naming a channel is not republishing it, and a handle in a post body is easy to place deliberately. The post counts beside each row below are distinct posts in which the handle appeared, from posts we have read on both sides — the “Named by N registered channels” figure above is a different count, of distinct NAMING CHANNELS rather than posts, and is not the sum of the rows under it.
Cite this entry
A live page changes as we take new readings, so a citation should name the measurement it is based on, not just the URL. The line below cites the subscriber count as measured 10 August 2026 — this entry's latest reading, not the date you are reading this.
“SQL Pro” (@sqlprofi), 4,948 subscribers as measured 10 August 2026. Telegram Register, tgregister.com/channel/sqlprofi.
Full measurement history, CC BY 4.0. Every reading this register holds for this entry, not just the latest one, as a dated, downloadable record: CSV · JSON. Free to use with attribution to tgregister.com. Each file carries its own generation timestamp, which is the figure to cite for exactly when the data was retrieved.