Automated Grading of SQL Statements

Automated Grading of SQL Statements
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#### Introduction

All experimental data are stored in Submission.sqlite, which is an SQLite
database file. It is recommended to use software such as DB browser or SQLite
expert to explore the database.

Tables related to SQL statements submitted by students
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Tables with names beginning with 'exercise_' are all related to SQL statements,
and two of them are most important. One is the exercise_result table, which
records most of the information related to the SQL statements submitted by
students, and the other is the exercises_exercise table, which records most of
the information related to exercises. **The student submissions are stored in
the 'submitted_answer' field of the exercise_result data table.**

Table 1 Description of exercise_result table.

| Field            | comment                                    | datatype |
|------------------|--------------------------------------------|----------|
| submission_id    | Submission ID                              | INT      |
| submitted_answer | SQL statement submitted by student         | TEXT     |
| submitted_time   | Time of submission                         | NUM      |
| answer           | Reference statement provided by tutors     | TEXT     |
| exercise_id      | Exercise ID                                | INT      |
| is_correct       | Mark whether the statement is correct      | INT      |
| student_id       | Student ID                                 | INT      |
| type             | Classification of statement                | TEXT     |
| difficulty       | The difficulty coefficient of the exercise | INT      |

Table 2 Description of exercises_exercise table.

| Field       | comment                         | datatype |
|-------------|---------------------------------|----------|
| id          | Exercise ID                     | INT      |
| short_title | short title of exercise         | TEXT     |
| preamble    | description of exercise         | TEXT     |
| difficulty  | coefficient of difficulty       | integer  |
| visible     | whether the exercise is visible | boolean  |
| priority    | the priority of exercise        | integer  |

Table 3 Description of exercises_benchmark table.

| Field         | comment                 | datatype |
|---------------|-------------------------|----------|
| Submission_id | Submission ID           | INT      |
| grade         | grade provided by tutor | REAL     |
| tutor         | tutor name              | TEXT     |

Table 4 Description of exercises_grade table.

| Field            | comment                                     | datatype |
|------------------|---------------------------------------------|----------|
| submission_id    | Submission ID                               | INT      |
| submitted_answer | SQL statement submitted by student          | TEXT     |
| grade            | provided by different approach              | REAL     |
| approach         | approach name                               | TEXT     |
| most_similar     | most similar statement to current statement | TEXT     |

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Please refer to db_schema.pdf for the database schema used in the experiment.