Prepare for the SQLD with concept learning, SQL practice exercises, 10 sets of mock exams, and FSRS review.
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SQLD Learning That You Won't Forget. How you review, rather than how many problems you solve, determines your success.
SQLmate is not just an app that increases the number of problems. It focuses on pinpointing your current weaknesses and bringing you back problems you've already solved just before you forget them. Because the cognitive science-based FSRS algorithm analyzes the forgetting curve for each problem to automatically determine the optimal review time, the amount of information retained differs significantly even with the same amount of time invested.
[Key Features]
Concept Learning
If you feel overwhelmed trying to solve problems, start by reviewing the concepts. The entire range of SQLD is divided into 138 lessons for sequential learning, and you can immediately verify your understanding of learned concepts through practice problems.
4,602 Problems, Entire SQLD Range
From understanding data modeling to SQL basics and applications. Produced in-house to reflect KDATA's official exam standards.
Detailed Explanations
Explanations are provided for every problem. You can move on without simply checking the answer, understanding the concepts behind why that answer is correct. While the more in-depth detailed explanations are a premium feature, some can be accessed and checked directly for free. SQL Practice Area
You can skip directly from the explanation and run the query for the problem yourself. The problem table is already uploaded, so it opens in your browser without installation or login. Try changing the conditions to see how the results change.
Various Solution Modes
You can choose to solve problems by subject or chapter. You can start with unsolved problems or gather only your weak chapters to focus on. A chapter-by-chapter shuffle mode that mixes problems from all subjects is also provided for free.
FSRS Smart Review
The app extends the review interval for questions you answer correctly and quickly shows you frequently missed questions again. You don't need to create a review schedule yourself; the app takes care of the problems you need to review today.
Review Notifications
With daily study reminders and FSRS review time notifications, it helps you maintain your study flow so you can revisit the material just when you are about to forget.
Weakness Analysis Heatmap
View the correct answer rate for each specific chapter at a glance. Identify your weak areas by color and jump directly to the solutions for that chapter. Error Notes and Review Box
Gather your incorrect answers and questions to review in one place. Group questions by cause—such as trap types, SQL syntax, or out-of-range errors—for review, and add your own notes to each question.
Practical Mock Tests
Provides 10 sets of 50-question, 90-minute mock tests, just like the actual exam. Scoring is based on a passing score, and your highest score and test history are managed.
Learning Statistics and Continuous Study
Check your daily problem-solving count, accuracy trends, and consecutive study days in real-time. Records that accumulate little by little each day help build consistency.
Exam Schedule D-Day
Check upcoming SQLD exam schedules directly from the home screen.
Light or Dark Themes
You can follow system settings or choose your own, ensuring comfortable viewing even when studying late at night.
Tablet Support
Study comfortably on tablets as well as mobile phones with a layout optimized for large screens.
Offline Study
Solve problems even without an internet connection. Study without interruption on subways or airplanes. [Content Guide]
SQLmate does not include past exam questions. This is because actual SQLD exam questions are not publicly available, and the copyright for past questions belongs to the administering body, the Korea Data Industry Promotion Agency (KDATA); therefore, copying and pasting them as is is not permitted. Instead, we have analyzed KDATA's question standards and created study questions tailored to the format and difficulty level of the actual exam. The questions are composed of core question types with a high probability of appearing on the exam, and we do not restore or duplicate past questions. This is a tool to aid learning and does not guarantee passing.
This app is an independent private learning tool designed to assist with SQLD study and is not affiliated with or representative of any government or public institution, such as the Korea Data Industry Promotion Agency (KDATA).
**Content Guide** [Recommended for]
Those preparing for SQLD for the first time
Job seekers and office workers aiming to pass through self-study
Those preparing for the next certification after passing the Information Processing Engineer certification
Those preparing for data-related careers as non-computer science majors
Those who want to study briefly using their commute time
[Terms and Conditions]
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