SQL Strategy

SQL, which is difficult to understand only looking at a reference book, can be easily mastered by learning while executing. This is the main content of this site.

1 Introduction
2 SQL Basics
3 Basics of SELECT statement (1)
4 Basics of SELECT statement (2)
5 Sort (ORDER BY)
6 Functions (SUM, MAX, MIN, AVG, COUNT)
7 Extract by range (BETWEEN)
8 Pattern search (LIKE)
9 Grouping (GROUP BY)
10 Selection criteria for grouped tables (HAVING)
11 Duplicate row elimination (DISTINCT)
12 INSERT statement
13 UPDATE statement
14 DELETE statement
15 Inquiry to multiple tables
16 Nested Inquiry

Normalization strategy

Normalization theory, which was not found in the Basic Information and IT Passport exam questions, can be mastered here for sure. This is an area that frequently appears on the exam, so be sure to keep it in check.

1 Introduction
2 Basis for understanding normalization
3 From non-normal form to first normal form
4 From first normal form to second normal form
5 From second normal form to third normal form
6 Let's solve past question.
7 Finally

SQL Strategy

SNS

SQL Strategy

Normalization strategy