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Oracle Master Silver SQL 2019(1Z0-071)
問題ID : 26508
問題を開く
DEPARTMENTS表とEMPLOYEES表の構造を確認して下さい。
![<img src="/mondai3/img/jpg/48988.jpg">](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19338/48988.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T031923Z&X-Amz-Security-Token=IQoJb3JpZ2luX2VjEAgaDmFwLW5vcnRoZWFzdC0xIkgwRgIhANHJuOowIP70c5JvzZjwVv5qS91hqIWdQFZzYJWrf%2BvoAiEAvoVVFMmtRzvvs5kU35dlS89gfzMOt4V6dNlhGoNwtKIqsQQI4v%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARAAGgw2MjM0Mjk4MjcyNzUiDH%2FzNF8qx%2BnHRiOCJSqFBAQWQnV37gSoyaGHp1Jz5xS766UNOpZxuBfnriUqNRkTRQvse4S%2BUx5wWq3Cq1N85EgDWHpTUdk0z0onEOaGztMin1WP6QWXrlX8SmK5wxvk8von2NK6jFMcwAQfaEH7twN%2BjyrnhKNxNFO5vt8vs0H%2FJXTjGK6ePeLRthQ4%2FxqLEtmuQ%2BYoUojAqQBWCEjP5KpAAje2xJqxViGg9iqYP0STI7gWVAYeEmv1nzs4AxvJNdf1fYRBilxZ2PIgn1mvR%2FK7dxbz2smHtg2HhzsZjaJ5H8WHqRLQINQrr714HX9u4k1RvZzzuCtmNDvgC93ASD8mKQlAuaAA1SGfG60tXKUayewaXZFPlGcR%2B6A1j7d5INESj%2BLzK0Jp2dP10GooOXm8UnTCLj2nkFFxMh9VIE64CY1avR%2F0kV72Po7FoTcVcuzoH2IbOrSgIyT8N4Ij8F5fOqcqbDdyhmNRfLmd0N7ZP25qoU6K3rIMeMWKgPzaeT54s2i%2Bnhszui3m0Sy9he9RwbFlf%2FMmaHob3lafQzjThxSkzqFbWm1mogY3tfKExSH1iRtyX1Y%2BAim4wtO1ZizqEDqMkW8SAzD0xxIneYuT3GPr66KWSCEHKHW6t20NRYGyXTEr%2FwELefBQKzfDPLRwL4OPSeHHkEUiypb763zevR2RhLks%2B4EKNse0Py4eASWiTbwwuP%2BQtQY6pQHuYZCSXCZiYnz1Mbqq4CBIMnYufh%2FzzOnVAmaVI9V%2FHpM72SD2qm%2Bk6YSrekCCOcmaa5EwsV9AQDxwXatoy96nbNYBSbjYNXQIq5ygpCHI03EDC%2FTaH%2B9sanKP4qnQopFS5G9SAJl1OdRKmgycdC3TW8IYhWC1%2BFhsTJeNsF824TVcPR4VGJbPfwr75zlJD9Jhh6YhJhq1UMNJaqEm5AFczAffBV0%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=ASIAZCJ2QHLFRAGVRWFZ%2F20240727%2Fap-northeast-1%2Fs3%2Faws4_request&X-Amz-SignedHeaders=host&X-Amz-Signature=695e078f3d39bb5e7777615a36e110de3a69d98aee22c938552699e6f29b7ae3)
![<img src="/mondai3/img/jpg/48861.jpg">](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19316/48861.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T031923Z&X-Amz-Security-Token=IQoJb3JpZ2luX2VjEAgaDmFwLW5vcnRoZWFzdC0xIkgwRgIhANHJuOowIP70c5JvzZjwVv5qS91hqIWdQFZzYJWrf%2BvoAiEAvoVVFMmtRzvvs5kU35dlS89gfzMOt4V6dNlhGoNwtKIqsQQI4v%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARAAGgw2MjM0Mjk4MjcyNzUiDH%2FzNF8qx%2BnHRiOCJSqFBAQWQnV37gSoyaGHp1Jz5xS766UNOpZxuBfnriUqNRkTRQvse4S%2BUx5wWq3Cq1N85EgDWHpTUdk0z0onEOaGztMin1WP6QWXrlX8SmK5wxvk8von2NK6jFMcwAQfaEH7twN%2BjyrnhKNxNFO5vt8vs0H%2FJXTjGK6ePeLRthQ4%2FxqLEtmuQ%2BYoUojAqQBWCEjP5KpAAje2xJqxViGg9iqYP0STI7gWVAYeEmv1nzs4AxvJNdf1fYRBilxZ2PIgn1mvR%2FK7dxbz2smHtg2HhzsZjaJ5H8WHqRLQINQrr714HX9u4k1RvZzzuCtmNDvgC93ASD8mKQlAuaAA1SGfG60tXKUayewaXZFPlGcR%2B6A1j7d5INESj%2BLzK0Jp2dP10GooOXm8UnTCLj2nkFFxMh9VIE64CY1avR%2F0kV72Po7FoTcVcuzoH2IbOrSgIyT8N4Ij8F5fOqcqbDdyhmNRfLmd0N7ZP25qoU6K3rIMeMWKgPzaeT54s2i%2Bnhszui3m0Sy9he9RwbFlf%2FMmaHob3lafQzjThxSkzqFbWm1mogY3tfKExSH1iRtyX1Y%2BAim4wtO1ZizqEDqMkW8SAzD0xxIneYuT3GPr66KWSCEHKHW6t20NRYGyXTEr%2FwELefBQKzfDPLRwL4OPSeHHkEUiypb763zevR2RhLks%2B4EKNse0Py4eASWiTbwwuP%2BQtQY6pQHuYZCSXCZiYnz1Mbqq4CBIMnYufh%2FzzOnVAmaVI9V%2FHpM72SD2qm%2Bk6YSrekCCOcmaa5EwsV9AQDxwXatoy96nbNYBSbjYNXQIq5ygpCHI03EDC%2FTaH%2B9sanKP4qnQopFS5G9SAJl1OdRKmgycdC3TW8IYhWC1%2BFhsTJeNsF824TVcPR4VGJbPfwr75zlJD9Jhh6YhJhq1UMNJaqEm5AFczAffBV0%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=ASIAZCJ2QHLFRAGVRWFZ%2F20240727%2Fap-northeast-1%2Fs3%2Faws4_request&X-Amz-SignedHeaders=host&X-Amz-Signature=f12c5799bbc9882f35f8fde2b7fbce47eb5a7fd86d54aacb095894c1f4577744)
2つの表を結合するSQL文としてエラーとなるものはどれですか(該当するものを全て選択して下さい)。
![<img src="/mondai3/img/jpg/48988.jpg">](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19338/48988.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T031923Z&X-Amz-Security-Token=IQoJb3JpZ2luX2VjEAgaDmFwLW5vcnRoZWFzdC0xIkgwRgIhANHJuOowIP70c5JvzZjwVv5qS91hqIWdQFZzYJWrf%2BvoAiEAvoVVFMmtRzvvs5kU35dlS89gfzMOt4V6dNlhGoNwtKIqsQQI4v%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARAAGgw2MjM0Mjk4MjcyNzUiDH%2FzNF8qx%2BnHRiOCJSqFBAQWQnV37gSoyaGHp1Jz5xS766UNOpZxuBfnriUqNRkTRQvse4S%2BUx5wWq3Cq1N85EgDWHpTUdk0z0onEOaGztMin1WP6QWXrlX8SmK5wxvk8von2NK6jFMcwAQfaEH7twN%2BjyrnhKNxNFO5vt8vs0H%2FJXTjGK6ePeLRthQ4%2FxqLEtmuQ%2BYoUojAqQBWCEjP5KpAAje2xJqxViGg9iqYP0STI7gWVAYeEmv1nzs4AxvJNdf1fYRBilxZ2PIgn1mvR%2FK7dxbz2smHtg2HhzsZjaJ5H8WHqRLQINQrr714HX9u4k1RvZzzuCtmNDvgC93ASD8mKQlAuaAA1SGfG60tXKUayewaXZFPlGcR%2B6A1j7d5INESj%2BLzK0Jp2dP10GooOXm8UnTCLj2nkFFxMh9VIE64CY1avR%2F0kV72Po7FoTcVcuzoH2IbOrSgIyT8N4Ij8F5fOqcqbDdyhmNRfLmd0N7ZP25qoU6K3rIMeMWKgPzaeT54s2i%2Bnhszui3m0Sy9he9RwbFlf%2FMmaHob3lafQzjThxSkzqFbWm1mogY3tfKExSH1iRtyX1Y%2BAim4wtO1ZizqEDqMkW8SAzD0xxIneYuT3GPr66KWSCEHKHW6t20NRYGyXTEr%2FwELefBQKzfDPLRwL4OPSeHHkEUiypb763zevR2RhLks%2B4EKNse0Py4eASWiTbwwuP%2BQtQY6pQHuYZCSXCZiYnz1Mbqq4CBIMnYufh%2FzzOnVAmaVI9V%2FHpM72SD2qm%2Bk6YSrekCCOcmaa5EwsV9AQDxwXatoy96nbNYBSbjYNXQIq5ygpCHI03EDC%2FTaH%2B9sanKP4qnQopFS5G9SAJl1OdRKmgycdC3TW8IYhWC1%2BFhsTJeNsF824TVcPR4VGJbPfwr75zlJD9Jhh6YhJhq1UMNJaqEm5AFczAffBV0%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=ASIAZCJ2QHLFRAGVRWFZ%2F20240727%2Fap-northeast-1%2Fs3%2Faws4_request&X-Amz-SignedHeaders=host&X-Amz-Signature=695e078f3d39bb5e7777615a36e110de3a69d98aee22c938552699e6f29b7ae3)
![<img src="/mondai3/img/jpg/48861.jpg">](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19316/48861.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T031923Z&X-Amz-Security-Token=IQoJb3JpZ2luX2VjEAgaDmFwLW5vcnRoZWFzdC0xIkgwRgIhANHJuOowIP70c5JvzZjwVv5qS91hqIWdQFZzYJWrf%2BvoAiEAvoVVFMmtRzvvs5kU35dlS89gfzMOt4V6dNlhGoNwtKIqsQQI4v%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARAAGgw2MjM0Mjk4MjcyNzUiDH%2FzNF8qx%2BnHRiOCJSqFBAQWQnV37gSoyaGHp1Jz5xS766UNOpZxuBfnriUqNRkTRQvse4S%2BUx5wWq3Cq1N85EgDWHpTUdk0z0onEOaGztMin1WP6QWXrlX8SmK5wxvk8von2NK6jFMcwAQfaEH7twN%2BjyrnhKNxNFO5vt8vs0H%2FJXTjGK6ePeLRthQ4%2FxqLEtmuQ%2BYoUojAqQBWCEjP5KpAAje2xJqxViGg9iqYP0STI7gWVAYeEmv1nzs4AxvJNdf1fYRBilxZ2PIgn1mvR%2FK7dxbz2smHtg2HhzsZjaJ5H8WHqRLQINQrr714HX9u4k1RvZzzuCtmNDvgC93ASD8mKQlAuaAA1SGfG60tXKUayewaXZFPlGcR%2B6A1j7d5INESj%2BLzK0Jp2dP10GooOXm8UnTCLj2nkFFxMh9VIE64CY1avR%2F0kV72Po7FoTcVcuzoH2IbOrSgIyT8N4Ij8F5fOqcqbDdyhmNRfLmd0N7ZP25qoU6K3rIMeMWKgPzaeT54s2i%2Bnhszui3m0Sy9he9RwbFlf%2FMmaHob3lafQzjThxSkzqFbWm1mogY3tfKExSH1iRtyX1Y%2BAim4wtO1ZizqEDqMkW8SAzD0xxIneYuT3GPr66KWSCEHKHW6t20NRYGyXTEr%2FwELefBQKzfDPLRwL4OPSeHHkEUiypb763zevR2RhLks%2B4EKNse0Py4eASWiTbwwuP%2BQtQY6pQHuYZCSXCZiYnz1Mbqq4CBIMnYufh%2FzzOnVAmaVI9V%2FHpM72SD2qm%2Bk6YSrekCCOcmaa5EwsV9AQDxwXatoy96nbNYBSbjYNXQIq5ygpCHI03EDC%2FTaH%2B9sanKP4qnQopFS5G9SAJl1OdRKmgycdC3TW8IYhWC1%2BFhsTJeNsF824TVcPR4VGJbPfwr75zlJD9Jhh6YhJhq1UMNJaqEm5AFczAffBV0%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=ASIAZCJ2QHLFRAGVRWFZ%2F20240727%2Fap-northeast-1%2Fs3%2Faws4_request&X-Amz-SignedHeaders=host&X-Amz-Signature=f12c5799bbc9882f35f8fde2b7fbce47eb5a7fd86d54aacb095894c1f4577744)
2つの表を結合するSQL文としてエラーとなるものはどれですか(該当するものを全て選択して下さい)。
正解
SELECT department_name, employee_name, salary FROM departments d JOIN employees e WHERE d.department_id = e.department_id;
SELECT d.department_name, e.employee_name, e.salary FROM departments d NATURAL JOIN employees e USING (department_id);
解説
選択肢のSQL文を1つずつ確認してみましょう。
・SELECT department_name, employee_name, salary FROM departments d JOIN employees e WHERE d.department_id = e.department_id;
JOIN句で結合する場合、結合条件はON句、またはUSING句に記述します。このSQL文のように等号(=)を使用するならばON句が必要ですが、WHERE句に結合条件が指定されておりエラーとなります。
・SELECT department_name, employee_name, salary FROM departments d LEFT OUTER JOIN employees e ON d.department_id = e.department_id;
LEFT OUTER JOINによる左側外部結合です。結合条件にJOIN句の左側に指定された表のデータは、結合条件に合致しない場合でも表示します。正しいSQL文です。
・SELECT d.department_name, e.employee_name, e.salary FROM departments d NATURAL JOIN employees e;
NATURAL JOINによる自然結合です。2つの表で共通の列である、DEPARTMENT_ID列とMANAGER_ID列の値に基いて結合します。正しいSQL文です。
・SELECT d.department_name, e.employee_name, e.salary FROM departments d NATURAL JOIN employees e USING (department_id);
NATURAL JOINとUSINGは1つの結合で同時に指定できないため、エラーとなります。
・SELECT d.department_name, e.employee_name, e.salary FROM departments d JOIN employees e USING (department_id);
USING句による等価結合です。2つの表のDEPARTMENT_ID列の値が等しい行を結合します。正しいSQL文です。
以上より、
・SELECT department_name, employee_name, salary FROM departments d JOIN employees e WHERE d.department_id = e.department_id;
・SELECT d.department_name, e.employee_name, e.salary FROM departments d NATURAL JOIN employees e USING (department_id);
が正解となります。
正解のSQL文の実行結果は次のようになります。
![【図を表示】](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19604/k49007.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T031923Z&X-Amz-Security-Token=IQoJb3JpZ2luX2VjEAgaDmFwLW5vcnRoZWFzdC0xIkgwRgIhANHJuOowIP70c5JvzZjwVv5qS91hqIWdQFZzYJWrf%2BvoAiEAvoVVFMmtRzvvs5kU35dlS89gfzMOt4V6dNlhGoNwtKIqsQQI4v%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARAAGgw2MjM0Mjk4MjcyNzUiDH%2FzNF8qx%2BnHRiOCJSqFBAQWQnV37gSoyaGHp1Jz5xS766UNOpZxuBfnriUqNRkTRQvse4S%2BUx5wWq3Cq1N85EgDWHpTUdk0z0onEOaGztMin1WP6QWXrlX8SmK5wxvk8von2NK6jFMcwAQfaEH7twN%2BjyrnhKNxNFO5vt8vs0H%2FJXTjGK6ePeLRthQ4%2FxqLEtmuQ%2BYoUojAqQBWCEjP5KpAAje2xJqxViGg9iqYP0STI7gWVAYeEmv1nzs4AxvJNdf1fYRBilxZ2PIgn1mvR%2FK7dxbz2smHtg2HhzsZjaJ5H8WHqRLQINQrr714HX9u4k1RvZzzuCtmNDvgC93ASD8mKQlAuaAA1SGfG60tXKUayewaXZFPlGcR%2B6A1j7d5INESj%2BLzK0Jp2dP10GooOXm8UnTCLj2nkFFxMh9VIE64CY1avR%2F0kV72Po7FoTcVcuzoH2IbOrSgIyT8N4Ij8F5fOqcqbDdyhmNRfLmd0N7ZP25qoU6K3rIMeMWKgPzaeT54s2i%2Bnhszui3m0Sy9he9RwbFlf%2FMmaHob3lafQzjThxSkzqFbWm1mogY3tfKExSH1iRtyX1Y%2BAim4wtO1ZizqEDqMkW8SAzD0xxIneYuT3GPr66KWSCEHKHW6t20NRYGyXTEr%2FwELefBQKzfDPLRwL4OPSeHHkEUiypb763zevR2RhLks%2B4EKNse0Py4eASWiTbwwuP%2BQtQY6pQHuYZCSXCZiYnz1Mbqq4CBIMnYufh%2FzzOnVAmaVI9V%2FHpM72SD2qm%2Bk6YSrekCCOcmaa5EwsV9AQDxwXatoy96nbNYBSbjYNXQIq5ygpCHI03EDC%2FTaH%2B9sanKP4qnQopFS5G9SAJl1OdRKmgycdC3TW8IYhWC1%2BFhsTJeNsF824TVcPR4VGJbPfwr75zlJD9Jhh6YhJhq1UMNJaqEm5AFczAffBV0%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=ASIAZCJ2QHLFRAGVRWFZ%2F20240727%2Fap-northeast-1%2Fs3%2Faws4_request&X-Amz-SignedHeaders=host&X-Amz-Signature=8e6c91bd902ef8c522caf94edfb6baaa60c5d374b07aecd6968b244eaa1bb4f2)
![【図を表示2】](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19605/kk49007.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T031923Z&X-Amz-Security-Token=IQoJb3JpZ2luX2VjEAgaDmFwLW5vcnRoZWFzdC0xIkgwRgIhANHJuOowIP70c5JvzZjwVv5qS91hqIWdQFZzYJWrf%2BvoAiEAvoVVFMmtRzvvs5kU35dlS89gfzMOt4V6dNlhGoNwtKIqsQQI4v%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARAAGgw2MjM0Mjk4MjcyNzUiDH%2FzNF8qx%2BnHRiOCJSqFBAQWQnV37gSoyaGHp1Jz5xS766UNOpZxuBfnriUqNRkTRQvse4S%2BUx5wWq3Cq1N85EgDWHpTUdk0z0onEOaGztMin1WP6QWXrlX8SmK5wxvk8von2NK6jFMcwAQfaEH7twN%2BjyrnhKNxNFO5vt8vs0H%2FJXTjGK6ePeLRthQ4%2FxqLEtmuQ%2BYoUojAqQBWCEjP5KpAAje2xJqxViGg9iqYP0STI7gWVAYeEmv1nzs4AxvJNdf1fYRBilxZ2PIgn1mvR%2FK7dxbz2smHtg2HhzsZjaJ5H8WHqRLQINQrr714HX9u4k1RvZzzuCtmNDvgC93ASD8mKQlAuaAA1SGfG60tXKUayewaXZFPlGcR%2B6A1j7d5INESj%2BLzK0Jp2dP10GooOXm8UnTCLj2nkFFxMh9VIE64CY1avR%2F0kV72Po7FoTcVcuzoH2IbOrSgIyT8N4Ij8F5fOqcqbDdyhmNRfLmd0N7ZP25qoU6K3rIMeMWKgPzaeT54s2i%2Bnhszui3m0Sy9he9RwbFlf%2FMmaHob3lafQzjThxSkzqFbWm1mogY3tfKExSH1iRtyX1Y%2BAim4wtO1ZizqEDqMkW8SAzD0xxIneYuT3GPr66KWSCEHKHW6t20NRYGyXTEr%2FwELefBQKzfDPLRwL4OPSeHHkEUiypb763zevR2RhLks%2B4EKNse0Py4eASWiTbwwuP%2BQtQY6pQHuYZCSXCZiYnz1Mbqq4CBIMnYufh%2FzzOnVAmaVI9V%2FHpM72SD2qm%2Bk6YSrekCCOcmaa5EwsV9AQDxwXatoy96nbNYBSbjYNXQIq5ygpCHI03EDC%2FTaH%2B9sanKP4qnQopFS5G9SAJl1OdRKmgycdC3TW8IYhWC1%2BFhsTJeNsF824TVcPR4VGJbPfwr75zlJD9Jhh6YhJhq1UMNJaqEm5AFczAffBV0%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=ASIAZCJ2QHLFRAGVRWFZ%2F20240727%2Fap-northeast-1%2Fs3%2Faws4_request&X-Amz-SignedHeaders=host&X-Amz-Signature=5f79bcb17072ae809c5692ea24433ec7556b7e1b17908677177860c5dfb2bfc0)
参考:
Oracle Databaseではいろいろな方法で表を結合することができます。主な結合方法は次の通りです。
・SELECT department_name, employee_name, salary FROM departments d JOIN employees e WHERE d.department_id = e.department_id;
JOIN句で結合する場合、結合条件はON句、またはUSING句に記述します。このSQL文のように等号(=)を使用するならばON句が必要ですが、WHERE句に結合条件が指定されておりエラーとなります。
・SELECT department_name, employee_name, salary FROM departments d LEFT OUTER JOIN employees e ON d.department_id = e.department_id;
LEFT OUTER JOINによる左側外部結合です。結合条件にJOIN句の左側に指定された表のデータは、結合条件に合致しない場合でも表示します。正しいSQL文です。
・SELECT d.department_name, e.employee_name, e.salary FROM departments d NATURAL JOIN employees e;
NATURAL JOINによる自然結合です。2つの表で共通の列である、DEPARTMENT_ID列とMANAGER_ID列の値に基いて結合します。正しいSQL文です。
・SELECT d.department_name, e.employee_name, e.salary FROM departments d NATURAL JOIN employees e USING (department_id);
NATURAL JOINとUSINGは1つの結合で同時に指定できないため、エラーとなります。
・SELECT d.department_name, e.employee_name, e.salary FROM departments d JOIN employees e USING (department_id);
USING句による等価結合です。2つの表のDEPARTMENT_ID列の値が等しい行を結合します。正しいSQL文です。
以上より、
・SELECT department_name, employee_name, salary FROM departments d JOIN employees e WHERE d.department_id = e.department_id;
・SELECT d.department_name, e.employee_name, e.salary FROM departments d NATURAL JOIN employees e USING (department_id);
が正解となります。
正解のSQL文の実行結果は次のようになります。
![【図を表示】](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19604/k49007.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T031923Z&X-Amz-Security-Token=IQoJb3JpZ2luX2VjEAgaDmFwLW5vcnRoZWFzdC0xIkgwRgIhANHJuOowIP70c5JvzZjwVv5qS91hqIWdQFZzYJWrf%2BvoAiEAvoVVFMmtRzvvs5kU35dlS89gfzMOt4V6dNlhGoNwtKIqsQQI4v%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARAAGgw2MjM0Mjk4MjcyNzUiDH%2FzNF8qx%2BnHRiOCJSqFBAQWQnV37gSoyaGHp1Jz5xS766UNOpZxuBfnriUqNRkTRQvse4S%2BUx5wWq3Cq1N85EgDWHpTUdk0z0onEOaGztMin1WP6QWXrlX8SmK5wxvk8von2NK6jFMcwAQfaEH7twN%2BjyrnhKNxNFO5vt8vs0H%2FJXTjGK6ePeLRthQ4%2FxqLEtmuQ%2BYoUojAqQBWCEjP5KpAAje2xJqxViGg9iqYP0STI7gWVAYeEmv1nzs4AxvJNdf1fYRBilxZ2PIgn1mvR%2FK7dxbz2smHtg2HhzsZjaJ5H8WHqRLQINQrr714HX9u4k1RvZzzuCtmNDvgC93ASD8mKQlAuaAA1SGfG60tXKUayewaXZFPlGcR%2B6A1j7d5INESj%2BLzK0Jp2dP10GooOXm8UnTCLj2nkFFxMh9VIE64CY1avR%2F0kV72Po7FoTcVcuzoH2IbOrSgIyT8N4Ij8F5fOqcqbDdyhmNRfLmd0N7ZP25qoU6K3rIMeMWKgPzaeT54s2i%2Bnhszui3m0Sy9he9RwbFlf%2FMmaHob3lafQzjThxSkzqFbWm1mogY3tfKExSH1iRtyX1Y%2BAim4wtO1ZizqEDqMkW8SAzD0xxIneYuT3GPr66KWSCEHKHW6t20NRYGyXTEr%2FwELefBQKzfDPLRwL4OPSeHHkEUiypb763zevR2RhLks%2B4EKNse0Py4eASWiTbwwuP%2BQtQY6pQHuYZCSXCZiYnz1Mbqq4CBIMnYufh%2FzzOnVAmaVI9V%2FHpM72SD2qm%2Bk6YSrekCCOcmaa5EwsV9AQDxwXatoy96nbNYBSbjYNXQIq5ygpCHI03EDC%2FTaH%2B9sanKP4qnQopFS5G9SAJl1OdRKmgycdC3TW8IYhWC1%2BFhsTJeNsF824TVcPR4VGJbPfwr75zlJD9Jhh6YhJhq1UMNJaqEm5AFczAffBV0%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=ASIAZCJ2QHLFRAGVRWFZ%2F20240727%2Fap-northeast-1%2Fs3%2Faws4_request&X-Amz-SignedHeaders=host&X-Amz-Signature=8e6c91bd902ef8c522caf94edfb6baaa60c5d374b07aecd6968b244eaa1bb4f2)
![【図を表示2】](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19605/kk49007.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T031923Z&X-Amz-Security-Token=IQoJb3JpZ2luX2VjEAgaDmFwLW5vcnRoZWFzdC0xIkgwRgIhANHJuOowIP70c5JvzZjwVv5qS91hqIWdQFZzYJWrf%2BvoAiEAvoVVFMmtRzvvs5kU35dlS89gfzMOt4V6dNlhGoNwtKIqsQQI4v%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARAAGgw2MjM0Mjk4MjcyNzUiDH%2FzNF8qx%2BnHRiOCJSqFBAQWQnV37gSoyaGHp1Jz5xS766UNOpZxuBfnriUqNRkTRQvse4S%2BUx5wWq3Cq1N85EgDWHpTUdk0z0onEOaGztMin1WP6QWXrlX8SmK5wxvk8von2NK6jFMcwAQfaEH7twN%2BjyrnhKNxNFO5vt8vs0H%2FJXTjGK6ePeLRthQ4%2FxqLEtmuQ%2BYoUojAqQBWCEjP5KpAAje2xJqxViGg9iqYP0STI7gWVAYeEmv1nzs4AxvJNdf1fYRBilxZ2PIgn1mvR%2FK7dxbz2smHtg2HhzsZjaJ5H8WHqRLQINQrr714HX9u4k1RvZzzuCtmNDvgC93ASD8mKQlAuaAA1SGfG60tXKUayewaXZFPlGcR%2B6A1j7d5INESj%2BLzK0Jp2dP10GooOXm8UnTCLj2nkFFxMh9VIE64CY1avR%2F0kV72Po7FoTcVcuzoH2IbOrSgIyT8N4Ij8F5fOqcqbDdyhmNRfLmd0N7ZP25qoU6K3rIMeMWKgPzaeT54s2i%2Bnhszui3m0Sy9he9RwbFlf%2FMmaHob3lafQzjThxSkzqFbWm1mogY3tfKExSH1iRtyX1Y%2BAim4wtO1ZizqEDqMkW8SAzD0xxIneYuT3GPr66KWSCEHKHW6t20NRYGyXTEr%2FwELefBQKzfDPLRwL4OPSeHHkEUiypb763zevR2RhLks%2B4EKNse0Py4eASWiTbwwuP%2BQtQY6pQHuYZCSXCZiYnz1Mbqq4CBIMnYufh%2FzzOnVAmaVI9V%2FHpM72SD2qm%2Bk6YSrekCCOcmaa5EwsV9AQDxwXatoy96nbNYBSbjYNXQIq5ygpCHI03EDC%2FTaH%2B9sanKP4qnQopFS5G9SAJl1OdRKmgycdC3TW8IYhWC1%2BFhsTJeNsF824TVcPR4VGJbPfwr75zlJD9Jhh6YhJhq1UMNJaqEm5AFczAffBV0%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=ASIAZCJ2QHLFRAGVRWFZ%2F20240727%2Fap-northeast-1%2Fs3%2Faws4_request&X-Amz-SignedHeaders=host&X-Amz-Signature=5f79bcb17072ae809c5692ea24433ec7556b7e1b17908677177860c5dfb2bfc0)
参考:
Oracle Databaseではいろいろな方法で表を結合することができます。主な結合方法は次の通りです。
![<img src="/mondai3/img/jpg/k49080.jpg">](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19550/k49080.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T031923Z&X-Amz-Security-Token=IQoJb3JpZ2luX2VjEAgaDmFwLW5vcnRoZWFzdC0xIkgwRgIhANHJuOowIP70c5JvzZjwVv5qS91hqIWdQFZzYJWrf%2BvoAiEAvoVVFMmtRzvvs5kU35dlS89gfzMOt4V6dNlhGoNwtKIqsQQI4v%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARAAGgw2MjM0Mjk4MjcyNzUiDH%2FzNF8qx%2BnHRiOCJSqFBAQWQnV37gSoyaGHp1Jz5xS766UNOpZxuBfnriUqNRkTRQvse4S%2BUx5wWq3Cq1N85EgDWHpTUdk0z0onEOaGztMin1WP6QWXrlX8SmK5wxvk8von2NK6jFMcwAQfaEH7twN%2BjyrnhKNxNFO5vt8vs0H%2FJXTjGK6ePeLRthQ4%2FxqLEtmuQ%2BYoUojAqQBWCEjP5KpAAje2xJqxViGg9iqYP0STI7gWVAYeEmv1nzs4AxvJNdf1fYRBilxZ2PIgn1mvR%2FK7dxbz2smHtg2HhzsZjaJ5H8WHqRLQINQrr714HX9u4k1RvZzzuCtmNDvgC93ASD8mKQlAuaAA1SGfG60tXKUayewaXZFPlGcR%2B6A1j7d5INESj%2BLzK0Jp2dP10GooOXm8UnTCLj2nkFFxMh9VIE64CY1avR%2F0kV72Po7FoTcVcuzoH2IbOrSgIyT8N4Ij8F5fOqcqbDdyhmNRfLmd0N7ZP25qoU6K3rIMeMWKgPzaeT54s2i%2Bnhszui3m0Sy9he9RwbFlf%2FMmaHob3lafQzjThxSkzqFbWm1mogY3tfKExSH1iRtyX1Y%2BAim4wtO1ZizqEDqMkW8SAzD0xxIneYuT3GPr66KWSCEHKHW6t20NRYGyXTEr%2FwELefBQKzfDPLRwL4OPSeHHkEUiypb763zevR2RhLks%2B4EKNse0Py4eASWiTbwwuP%2BQtQY6pQHuYZCSXCZiYnz1Mbqq4CBIMnYufh%2FzzOnVAmaVI9V%2FHpM72SD2qm%2Bk6YSrekCCOcmaa5EwsV9AQDxwXatoy96nbNYBSbjYNXQIq5ygpCHI03EDC%2FTaH%2B9sanKP4qnQopFS5G9SAJl1OdRKmgycdC3TW8IYhWC1%2BFhsTJeNsF824TVcPR4VGJbPfwr75zlJD9Jhh6YhJhq1UMNJaqEm5AFczAffBV0%3D&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=ASIAZCJ2QHLFRAGVRWFZ%2F20240727%2Fap-northeast-1%2Fs3%2Faws4_request&X-Amz-SignedHeaders=host&X-Amz-Signature=dd2d19497315be0a811a26765b40509daa2dac05c8d6033711da8ef4d1a77764)
表接頭辞
公開日 2023/03/27
自然結合とusingを利用の場合は、結合列に表接頭辞が使えないはず。
問題がおかしいのではないか
C
CafeLate
2023/03/27 17:05
エラーとなるSQL文を選ぶ問題ですが、それは大丈夫ですか?
実際にLiveSQLで実行すると正解の選択肢はエラーとなり、それ以外は正常に結果が帰ってきます。
コメント
この投稿に対して返信しませんか?
r reo_tanabe
2023/06/26 11:20
今回の結合条件はdepartment_idですが、department_idに関して表接頭辞が使われていない(Select文で選ばれていない)ので、エラーにはならないのではないでしょうか。