正規表現(Regular Expression) vs Learn SQL

正規表現とは、『メタ文字(文字の情報、つまり"0"なら数字、"a"なら半角英字など)を利用して、文字列を表現すること』です。 １つメタ文字を紹介すると、"."(ドット)は『なんでも良い１文字』です。 例えば、正規表現『あ.す』に一致する文字は 『あいす』、『あきす』や『あーす』などなど...。 メタ文字を複数組み合わせることで膨大な文章の中から、電話番号のみなどの、特定の文字列だけ検索することが容易になります。 正規表現を覚えるために３つの機能を用意しています。 ①基本的な正規表現の一覧機能 →メタ文字の使い方や、正規表現(メタ文字の組み合わせ)の一覧が閲覧可能です。 ②正規表現を学ぶための機能 →難易度別に問題を用意しました。４択形式です。 全部回答すると、選択肢ごとに振り返りもできるようにしています。 合計で80問程度作りましたが、今後増やしていこうと思っています。(ネタを提供していただけると幸いです。) ③自由に正規表現を確認する機能 →自由に正規表現を確認できる画面を用意しています。 正規表現の入力補助機能や、フラグによる正規表現もあります。 ※『おいおい、正規表現の使い方間違っているぞ!!』、『この正規表現しってると便利だぞ!!』などありましたら、お手数ですがご連絡いただけると幸いですm(_ _)m※

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