Translation guide
The term 'structured query language' refers to SQL, a programming language for managing databases. In Japanese, it is almost always referred to by the acronym 'SQL' (pronounced エスキューエル or シークェル). The full translated term exists but is rarely used.
Referring to the programming language SQL itself.
The standard way to refer to SQL in Japanese. The acronym is used directly, often in all caps. Pronunciation is usually エスキューエル, but シークェル is also understood.
このシステムはSQLを使っています。
This system uses SQL.
SQLの知識が必要です。
Knowledge of SQL is required.
The literal translation of 'structured query language'. This is a technical term that is rarely used in practice; most people simply say SQL. It may appear in formal documentation or textbooks.
構造化照会言語（SQL）はデータベース管理に使われる。
Structured Query Language (SQL) is used for database management.
In Japanese, SQL is most commonly pronounced エスキューエル (esu kyū eru), following the English letter names. The pronunciation シークェル (shīkweru), from 'sequel', is also used but less common. When speaking, エスキューエル is the safer choice.