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235Scenarios are inspired by analytics, reporting, and application development workflows.</li> 236 <li><strong>Multi-engine validation</strong><br>Queries are verified against real database engines used in industry (for example MySQL, PostgreSQL, MS SQL Server, and Firebird).</li> 237 <li><strong>Progressive difficulty</strong><br>Task sets are structured from fundamentals to advanced topics such as joins, window functions, and performance-aware querying.</li> 238 <li><strong>Continuous review loop</strong><br>We monitor user feedback and update tasks, expected answers, and explanations to keep content accurate.</li> 239 </ul> 240 <p><strong>Public profiles and project identity:</strong></p> 241 <ul> 242 <li><strong>LinkedIn</strong>: <a href="https://www.linkedin.com/company/sqltest/" target="_blank" rel="noopener">SQLTest on LinkedIn</a></li> 243 <li><strong>GitHub</strong>: <a href="https://github.com/rozhnev/sqltest" target="_blank" rel="noopener">SQLTest source repository</a></li> 244 </ul> 245 </div> 246 </div> 247 </div> 248 <div class="section"> 249 <div> 250 <div class="color-block" style="background-color: #E5F7EB;"> 251 <img src="/images/about-for-students.png" alt="SQL learning for students on SQLTest.online" style="width: 90%;"> 252 <div> 253 <div> 254 <b>Want to learn Structured Query Language</b><br>to confidently work with data? 255 </div> 256 <div class="fake-button"> 257 That's definitely me :) 258 </div> 259 </div> 260 </div> 261 <div class="color-block" style="background-color: #FEF5F5;"> 262 <img src="/images/about-for-devs.png" alt="SQL practice for developers and analysts" style="width: 90%;"> 263 <div> 264 <div> 265 <b>Or maybe you are an experienced developer</b><br>looking to expand your knowledge and prepare for tough technical interviews? 266 </div> 267 <div class="fake-button"> 268 Yes, that's me! 269 </div> 270 </div> 271 </div> 272 </div> 273 </div> 274 <div class="section colored"> 275 <div class="blue-block"> 276 <h2>SQLTest.online is the perfect place for you!</h2> 277 <a href="/en/" class="button white"> 278 Start training â 279 </a> 280 </div> 281 </div> 282 <div class="section not-colored"> 283 <div> 284 <div class="section-column" style="padding: 0 0 0 2rem; white-space: nowrap;"> 285 <b>What will you get?</b> 286 </div> 287 <div class="section-column"> 288 <ul> 289 <li><b>Solid SQL knowledge</b><br> Understand the basics of the language and learn to write efficient queries.</li> 290 <li><b>Practical skills</b><br> Gain experience working with real data.</li> 291 <li><b>Confidence</b><br> Successfully solving tasks will boost your self-esteem and prepare you for any SQL challenges.</li> 292 </ul> 293 <a href="/en/playground/" class="button green about-cta-inline"> 294 Try SQL Playground â 295 </a> 296 </div> 297 </div> 298 </div> 299 <div class="section not-colored"> 300 <div style="width: 100%;"><b>Who is SQLTest.online for?</b></div> 301 <div> 302 <div style="display: flex; flex-flow: row wrap; justify-content: space-between; gap: 1rem;"> 303 <div class="section-column colored column30"> 304 <img src="/images/graduation-cap.png" alt="Graduation cap icon, symbol of completing an SQL course" width="64" height="64" style="height: 64px;"> 305 <div> 306 <div class="bold">Students</div> 307 <div style="font-size: small; margin-top: 0.5rem;">Learn SQL as part of your curriculum or for self-study.</div> 308 </div> 309 </div> 310 <div class="section-column colored column30"> 311 <img src="/images/technologist.png" alt="Developer icon, symbol of professional growth" width="65" height="64" style="height: 64px;"> 312 <div> 313 <div class="bold">Developers</div> 314 <div style="font-size: small; margin-top: 0.5rem;">Improve your skills for working with databases in projects.</div> 315 </div> 316 </div> 317 <div class="section-column colored column30"> 318 <img src="/images/bar-chart.png" alt="Data analytics icon, symbol of working with SQL" width="65" height="64" style="height: 64px;"> 319 <div> 320 <div class="bold">Data Analysts</div> 321 <div style="font-size: small; margin-top: 0.5rem;">Gain practical experience working with SQL for data analysis.</div> 322 </div> 323 </div> 324 </div> 325 </div> 326 </div> 327 <div class="section not-colored"> 328 <div style="width: 100%;"><b>How to start?</b></div> 329 <div> 330 <div style="display: flex; flex-flow: row wrap; justify-content: space-between; gap: 1rem;"> 331 <div class="section-column column30"> 332 <img src="/images/start1.png" alt="Step 1: open SQLTest.online tasks section" width="281" height="150" style="height: 150px;"> 333 <div> 334 <div class="bold"><span style="color: var(--light-h1-color);">1. </span>Visit the website</div> 335 <div style="font-size: small; margin-top: 0.5rem;">Go to SQLTest.online and select the "Tasks" section</div> 336 </div> 337 </div> 338 <div class="section-column column30"> 339 <img src="/images/start2.png" alt="Step 2: choose an SQL task category" width="281" height="150" style="height: 150px;"> 340 <div> 341 <div class="bold"><span style="color: var(--light-h1-color);">2. </span>Select a category</div> 342 <div style="font-size: small; margin-top: 0.5rem;">Choose the topic or difficulty level that interests you</div> 343 </div> 344 </div> 345 <div class="section-column column30"> 346 <img src="/images/start3.png" alt="Step 3: solve SQL tasks in the trainer" width="268" height="150" style="height: 150px;"> 347 <div> 348 <div class="bold"><span style="color: var(--light-h1-color);">3. </span>Solve tasks</div> 349 <div style="font-size: small; margin-top: 0.5rem;">Apply your SQL knowledge to solve the given tasks</div> 350 </div> 351 </div> 352 </div> 353 <div class="about-cta-center"> 354 <a href="/en/" class="button green"> 355 Go to tasks â 356 </a> 357 </div> 358 </div> 359 </div> 360 <div class="section not-colored"> 361 <div> 362 <div class="section-column" style="padding: 0 0 0 2rem; white-space: nowrap;"> 363 <b>Why choose us?</b> 364 </div> 365 <div class="section-column" style="max-width: 50rem;"> 366 <ul> 367 <li><strong>Interactive learning</strong><br>Solve various SQL tasks directly in the browser. No need to install additional programs or set up an environment.</li> 368 <li><strong>Variety of databases</strong><br>Practice on popular databases such as MySQL, PostgreSQL, MS SQL Server, and Firebird.</li> 369 <li><strong>Constant updates</strong><br>We regularly add new tasks so you always find interesting challenges.</li> 370 <li><strong>Detailed statistics</strong><br>
370Track your progress, analyze mistakes, and improve your results.</li> 371 <li><strong>Community</strong><br>Interact with other users, share experiences, and get help.</li> 372 </ul> 373 </div> 374 </div> 375 </div> 376 <div class="section not-colored"> 377 <div> 378 <div class="section-column" style="padding: 0 0 0 2rem; white-space: nowrap;"> 379 <b>Frequently asked questions</b> 380 </div> 381 <div class="section-column" style="max-width: 50rem;"> 382 <div class="about-faq-item"> 383 <div class="bold about-faq-question">What is SQLTest.online and who builds it?</div> 384 <div>SQLTest.online is an interactive platform for learning and practicing SQL. It is built by contributors with practical experience in SQL training, backend engineering, and data workflows.</div> 385 </div> 386 <div class="about-faq-item"> 387 <div class="bold about-faq-question">How can I practice SQL online with real database engines?</div> 388 <div>You can solve SQL tasks directly in the browser. Exercises are validated on real engines such as MySQL, PostgreSQL, MS SQL Server, and Firebird.</div> 389 </div> 390 <div class="about-faq-item"> 391 <div class="bold about-faq-question">How many SQL exercises are available for beginners and intermediate learners?</div> 392 <div>The platform currently offers 398+ practical SQL exercises organized by topic and difficulty, from fundamentals to advanced query patterns.</div> 393 </div> 394 <div class="about-faq-item"> 395 <div class="bold about-faq-question">Can SQLTest.online help with SQL interview preparation?</div> 396 <div>Yes. Task sets cover joins, aggregations, subqueries, window functions, and other topics commonly asked in SQL technical interviews.</div> 397 </div> 398 <div class="about-faq-item"> 399 <div class="bold about-faq-question">Where can I verify that SQLTest.online is a real project?</div> 400 <div>You can verify project identity through public profiles on LinkedIn and GitHub, with additional community presence in Telegram.</div> 401 </div> 402 <a href="/en/test/start" class="button green about-cta-bottom"> 403 Take SQL test â 404 </a> 405 </div> 406 </div> 407 </div> 408 <div class="section colored"> 409 <div class="blue-block"> 410 <h4>Everyone interested in programming</h4> 411 <h2>Expand your horizons and learn a new language.</h2> 412 <a href="https://telegram.me/sqlize" target="_blank" class="button white"> 413 Join our community! â 414 </a> 415 </div> 416 </div> 417 <div class="section not-colored"> 418 <div style="width: 100%;"> 419 <div class="section-column" style="width: 65%;"> 420 <h2>Follow our news on social media</h2> 421 <h4>and subscribe to our newsletter to stay updated with the latest news.</h4> 422 </div> 423 <div class="section-column column30" style="display: flex; flex-flow: row wrap; justify-content: space-around;"> 424 <a href="https://telegram.me/sqlize" target="_blank"class="social-media-link"> 425 <div> 426 <img src="/images/telegram_logo.png" alt="Telegram logo"> 427 Telegram 428 </div> 429 </a> 430 <a href="https://www.linkedin.com/company/sqltest/" target="_blank"class="social-media-link"> 431 <div> 432 <img src="/images/linkedin_logo.png" alt="LinkedIn logo"> 433 Linkedin 434 </div> 435 </a> 436 </div> 437 </div> 438 </div> 439 <div class="section bottom colored"> 440 <div> 441 <div class="credits"> 442 <div> 443 Many thanks 444 for contributing to the project: 445 <a href="/en/donate" target="_self" id="donate-btn"> 446 <button class="button green"><span><span class="currency">$</span> Keep SQLtest Free</span></button> 447 </a> 448 </div> 449 <div> 450 <a style="background: #EFFAB2; color: #79A01F; rotate: -3deg;" href ="https://telegram.me/artembuenas" target="_blank">Artem Latyshev</a> 451 <a style="background: #BFFDC9; color: #37B679; rotate: 2deg;" href ="https://telegram.me/alexgureev25" target="_blank">Alexander Gureev</a> 452 <a style="background: #FFE8A5; color: #D18328; rotate: -2deg;" href ="https://telegram.me/basanogijoe" target="_blank">Georgy Grigorchuk</a> 453 <a style="background: deepskyblue; color: whitesmoke;rotate: 4deg;" href="mailto:[email protected]" target="_blank">Elena Selsky</a> 454 <a style="background: #069adf; color: #300e95; rotate: -1deg;" href ="" target="_blank">Vladimir Revyakin</a> 455 </div> 456 </div> 457 </div> 458 </div> 459</article> 460 </main> 461 <footer> 462 <div class="footer-links"> 463 <div> 464 © 2023-2026 SQLtest.online 465 </div> 466 <div> 467 Have a question? <a target="_blank" href="https://telegram.me/sqltest_online" class="">
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