助け合いフォーラム
Oracle Master Silver SQL 2019(1Z0-071)
問題ID : 26861
問題を開く
外部結合の説明として正しいものはどれですか(該当するものを全て選択して下さい)。
正解
結合条件を満たす行と満たさない行の両方を取り出す
Oracle独自の結合構文には完全外部結合はない
解説
結合条件を満たしたデータのみを取り出すのではなく、検索条件を満たしていないデータも一緒に取り出す方法を外部結合といいます。
Oracle独自の結合構文では外部結合演算子(+)を使用して外部結合を行えますが、完全外部結合は行えません。
以上より、
・結合条件を満たす行と満たさない行の両方を取り出す
・Oracle独自の結合構文には完全外部結合はない
が正解となります。
その他の選択肢については以下のとおりです。
・結合条件を満たす行のみを取り出す
結合条件を満たす行のみを取り出す結合を内部結合といいます。
・結合条件を満たさない行のみを取り出す
外部結合では、結合条件を満たす行と満たさない行の両方を取り出します。
・NULL値を持たない列のみ結合できる
NULL値を持つ列を結合でき、結合条件を満たさない行も取り出せます。
Oracle独自の結合構文では外部結合演算子(+)を使用して外部結合を行えますが、完全外部結合は行えません。
以上より、
・結合条件を満たす行と満たさない行の両方を取り出す
・Oracle独自の結合構文には完全外部結合はない
が正解となります。
その他の選択肢については以下のとおりです。
・結合条件を満たす行のみを取り出す
結合条件を満たす行のみを取り出す結合を内部結合といいます。
・結合条件を満たさない行のみを取り出す
外部結合では、結合条件を満たす行と満たさない行の両方を取り出します。
・NULL値を持たない列のみ結合できる
NULL値を持つ列を結合でき、結合条件を満たさない行も取り出せます。
参考
結合条件を満たしたデータのみを取り出すのではなく、結合条件を満たしていないデータも一緒に取り出す方法を外部結合といいます(結合条件を満たすデータのみを取り出す方法を内部結合といいます)。
外部結合には、次の3つの方法があります。
![【図を表示】](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19603/k49003.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T042116Z&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=9e7d45d57d8b0914f92e22511d6e409eb44b23063e41921dc77c947bf7befdbe)
SELECT [表接頭辞.]列名 [, [表接頭辞.]列名 ...]
FROM 表名1
{LEFT | RIGHT | FULL} [OUTER] JOIN 表名2
ON 結合条件 ;
左側外部結合は結合条件を満たすデータと、JOIN句の左側に指定された表のデータを全て取り出す結合です。
![【図を表示2】](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19597/kk49003.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T042116Z&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=833fdf746c434d44a8526568899831bb58db6c20071bebb72c5591d7d236d69d)
右側外部結合は結合条件を満たすデータと、JOIN句の右側に指定された表のデータを全て取り出す結合です。
![<img src="/mondai3/img/jpg/k49005.jpg">](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19598/k49005.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T042116Z&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=a536fcfddf16fa1c468935f7088d9ddccc2dba37e269251edb6a01aef0fe50c9)
完全外部結合はJOIN句の左右に指定された表のデータを条件を満たしていないデータも含めて全て取り出す結合です。
![<img src="/mondai3/img/jpg/k49011.jpg">](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19599/k49011.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T042116Z&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=b94c1aac7f46d45a4ec119bd6459d5d4e813e02c6db4d3425ca2e1551eae220f)
また、Oracle独自の結合構文で外部結合を行えます。その際は外部結合演算子(+)を使用します。
Oracle独自の外部結合構文は次のとおりです。
SELECT [表接頭辞.]列名 [, [表接頭辞.]列名 ...]
FROM 表名1, 表名2
WHERE [表接頭辞1.]列名[(+)] = [表接頭辞2.]列名[(+)]
[AND 結合条件以外の条件];
Oracle独自の結合構文での外部結合では、WHERE句に指定した条件の左側に(+)をつけると右側外部結合、右側につけると左側外部結合の結果と等しくなります。
![<img src="/mondai3/img/jpg/kk49004.jpg">](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19600/kk49004.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T042116Z&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=c812deb8fc3c87affe07524d72944ef732966a5b1cb58b933b3ddf3055eae213)
![<img src="/mondai3/img/jpg/kkk49004.jpg">](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19601/kkk49004.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T042116Z&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=8a1cddfd7b08d92e9cc8b2e46b51b8816beb743ff86333a55099536acf600e23)
なお、Oracle独自の結合構文での外部結合では、完全外部結合は行えません。WHERE句の条件の両方に(+)をつけるとエラーとなります。
完全外部結合には FULL [OUTER] JOINを使用します。
![<img src="/mondai3/img/jpg/kkkk49004.jpg">](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19602/kkkk49004.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T042116Z&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=935a430f7ade263e988f001da73635785ba070fb4bea06df0a51abef3136b83a)
外部結合には、次の3つの方法があります。
![【図を表示】](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19603/k49003.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T042116Z&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=9e7d45d57d8b0914f92e22511d6e409eb44b23063e41921dc77c947bf7befdbe)
SELECT [表接頭辞.]列名 [, [表接頭辞.]列名 ...]
FROM 表名1
{LEFT | RIGHT | FULL} [OUTER] JOIN 表名2
ON 結合条件 ;
左側外部結合は結合条件を満たすデータと、JOIN句の左側に指定された表のデータを全て取り出す結合です。
![【図を表示2】](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19597/kk49003.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T042116Z&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=833fdf746c434d44a8526568899831bb58db6c20071bebb72c5591d7d236d69d)
SQLを表示
SELECT emp.employee_name, mgr.employee_name
FROM employees emp LEFT OUTER JOIN employees mgr
ON emp.manager_id = mgr.employee_id;
FROM employees emp LEFT OUTER JOIN employees mgr
ON emp.manager_id = mgr.employee_id;
右側外部結合は結合条件を満たすデータと、JOIN句の右側に指定された表のデータを全て取り出す結合です。
![<img src="/mondai3/img/jpg/k49005.jpg">](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19598/k49005.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T042116Z&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=a536fcfddf16fa1c468935f7088d9ddccc2dba37e269251edb6a01aef0fe50c9)
SQLを表示
SELECT e.employee_name, j.job_name
FROM employees e RIGHT OUTER JOIN jobs j
ON e.job_id = j.job_id;
FROM employees e RIGHT OUTER JOIN jobs j
ON e.job_id = j.job_id;
完全外部結合はJOIN句の左右に指定された表のデータを条件を満たしていないデータも含めて全て取り出す結合です。
![<img src="/mondai3/img/jpg/k49011.jpg">](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19599/k49011.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T042116Z&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=b94c1aac7f46d45a4ec119bd6459d5d4e813e02c6db4d3425ca2e1551eae220f)
SQLを表示
SELECT emp.employee_name, mgr.employee_name
FROM employees emp FULL OUTER JOIN employees mgr
ON emp.manager_id = mgr.employee_id;
FROM employees emp FULL OUTER JOIN employees mgr
ON emp.manager_id = mgr.employee_id;
また、Oracle独自の結合構文で外部結合を行えます。その際は外部結合演算子(+)を使用します。
Oracle独自の外部結合構文は次のとおりです。
SELECT [表接頭辞.]列名 [, [表接頭辞.]列名 ...]
FROM 表名1, 表名2
WHERE [表接頭辞1.]列名[(+)] = [表接頭辞2.]列名[(+)]
[AND 結合条件以外の条件];
Oracle独自の結合構文での外部結合では、WHERE句に指定した条件の左側に(+)をつけると右側外部結合、右側につけると左側外部結合の結果と等しくなります。
![<img src="/mondai3/img/jpg/kk49004.jpg">](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19600/kk49004.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T042116Z&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=c812deb8fc3c87affe07524d72944ef732966a5b1cb58b933b3ddf3055eae213)
SQLを表示
SELECT p.category, p.name, o.name
FROM prod p, oldprod o
WHERE p.category(+) = o.category;
SELECT p.category, p.name, o.name
FROM prod p RIGHT OUTER JOIN oldprod o
ON p.category = o.category;
FROM prod p, oldprod o
WHERE p.category(+) = o.category;
SELECT p.category, p.name, o.name
FROM prod p RIGHT OUTER JOIN oldprod o
ON p.category = o.category;
![<img src="/mondai3/img/jpg/kkk49004.jpg">](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19601/kkk49004.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T042116Z&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=8a1cddfd7b08d92e9cc8b2e46b51b8816beb743ff86333a55099536acf600e23)
SQLを表示
SELECT p.category, p.name, o.name
FROM prod p, oldprod o
WHERE p.category = o.category(+);
SELECT p.category, p.name, o.name
FROM prod p LEFT OUTER JOIN oldprod o
ON p.category = o.category;
FROM prod p, oldprod o
WHERE p.category = o.category(+);
SELECT p.category, p.name, o.name
FROM prod p LEFT OUTER JOIN oldprod o
ON p.category = o.category;
なお、Oracle独自の結合構文での外部結合では、完全外部結合は行えません。WHERE句の条件の両方に(+)をつけるとエラーとなります。
完全外部結合には FULL [OUTER] JOINを使用します。
![<img src="/mondai3/img/jpg/kkkk49004.jpg">](https://ping-t-production-strg.s3.ap-northeast-1.amazonaws.com/uploads/question_image/file/19602/kkkk49004.jpg?X-Amz-Expires=600&X-Amz-Date=20240727T042116Z&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=935a430f7ade263e988f001da73635785ba070fb4bea06df0a51abef3136b83a)
SQLを表示
SELECT p.category, p.name, o.name
FROM prod p, oldprod o
WHERE p.category(+) = o.category(+);
SELECT p.category, p.name, o.name
FROM prod p FULL OUTER JOIN oldprod o
ON p.category = o.category;
FROM prod p, oldprod o
WHERE p.category(+) = o.category(+);
SELECT p.category, p.name, o.name
FROM prod p FULL OUTER JOIN oldprod o
ON p.category = o.category;
Full outer joinは完全外部結合ではないのか
s
sarann
公開日 2022/11/22
Oracleではfull outer joinにて完全外部結合が出来ると思っています。
問題ではOracle独自構文としての完全外部結合はないと記載がありますが、
もし解答が合っている場合、
何をもって独自構文とするのか知りたいです。
q
quensan
2022/11/24 12:26
FULL OUTER JOINはANSI SQLの構文で、Oracle独自構文は外部結合演算子(+)を使う構文です。
26861の参考や26932、下記のサイトがわかりやすいかもしれません。
https://blogs.oracle.com/oraclemaster/post/om-silver-sql-2019-seminar-13
Oracle構文による結合
コメント
この投稿に対して返信しませんか?
s sarann
2022/12/25 20:46
参照先のサイト、大変参考になりました。理解できました、ありがとうございます。