{"id":195,"date":"2021-03-22T14:54:38","date_gmt":"2021-03-22T14:54:38","guid":{"rendered":"https:\/\/blogs.glowscotland.org.uk\/sh\/ahscomputingsql\/?page_id=195"},"modified":"2021-03-25T15:36:53","modified_gmt":"2021-03-25T15:36:53","slug":"primary-key","status":"publish","type":"page","link":"https:\/\/blogs.glowscotland.org.uk\/sh\/ahscomputingsql\/creating-a-database\/primary-key\/","title":{"rendered":"Primary &amp; Foreign Keys"},"content":{"rendered":"<h1><span style=\"color: #339966\">Level &#8211; National 5+<\/span><\/h1>\n<h1>Primary Key<\/h1>\n<p>Every table should have a primary key &#8211; a unique identifier for each record.<\/p>\n<p>Primary keys are required (Not Null), and\u00a0must be unique<\/p>\n<ul>\n<li>Right-click on the Table name<\/li>\n<li>Select &#8220;Modify table&#8221;<\/li>\n<li>Tick the NN, PK and U options for the primary key<br \/>\n<img decoding=\"async\" class=\"alignnone size-full wp-image-301\" src=\"https:\/\/blogs.glowscotland.org.uk\/sh\/public\/ahscomputingsql\/uploads\/sites\/3269\/2021\/03\/24122947\/DB4SQL-primary-key.png\" alt=\"\" width=\"610\" height=\"82\" srcset=\"https:\/\/blogs.glowscotland.org.uk\/sh\/public\/ahscomputingsql\/uploads\/sites\/3269\/2021\/03\/24122947\/DB4SQL-primary-key.png 610w, https:\/\/glow-prod-sh.s3.eu-west-1.amazonaws.com\/sh\/public\/ahscomputingsql\/uploads\/sites\/3269\/2021\/03\/24122947\/DB4SQL-primary-key-300x40.png?X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&amp;X-Amz-Security-Token=IQoJb3JpZ2luX2VjELX%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCWV1LXdlc3QtMSJGMEQCIBJhAojVHJBWMswjNI7hwVeFC7xTPKkGPmapajJCNPrhAiB6QI3iuWz%2FA0gb6zTkrKhplCOB96oK%2BB%2BqWdRRay%2F6TCq5BQh%2BEAUaDDI3MzU3MDE5NTQzMyIM33cIKemvJ2eVvKnqKpYFgpIbp70DiwF5DxnMSFFmjW6ZiMJSc%2B3yuLO2RneTSG8d1sI7iZqIznKFCQ9MM2LLjKCbaJICtjDVmtUU3t7H2J8VbF0Itq%2Fa180Qb%2FQKdovgF6lGfJqTPVqf24JYmt52cu5OBCqFNtW%2B7ddBiY6oggGtbGq%2BQDhotdHK4RI%2Bt7Pbxy3na%2BeM3tzaxERW5UmmBsXfjo6z0kve8edHU0EWO6kA%2F1OqI8UznKNgoi%2Fo%2FqfK2XGwA7YoqEvAgil%2F5CBduVy06SoLw04iVdn9449z2ucXumvI67Dk05Bf%2Fc7tMlQ0S%2F7YKGH7hgfbntS8l%2F1Mwzdz7OQl6ryPp8LJUzBxiLfbEWqhblA1oz3Lp6qk%2FkRkozlOo%2FADYokL2Puziq4i9fHcCxtOL7SAvL7Wra%2F3sfxXMh8NJCBRClJkb%2F9fnt%2FGA%2BpkIHChGbfxR64bQkdDyVPswdZ7efhIoE5jEZNiQzXz2NKo8ELlHldxqrbGxkgEr%2FzfcdSddg3BCL3YV8gRPqNSvzEl08EiKT1DPuv8ggWym%2B4oeF3BvXML0FNjtu0dalqTJ8Gjl94bre3dj16rsfip1K3vxgXjxqZMVVbCSzcIw5O0OpFLXaWpFkqKN4OHaFjtLGJcQj%2Fz%2BOGHHMpaSSEVOhqMJjgJiKHBuVI5NTQ2xLniHvFmk%2FXpmuOvxNc0l%2FONyJs599c%2FtaSs2poGNu1qRUrtfQYQmVtEjgegWkN6PVFqPLz7gRHVhnIC%2FXnSkhabPnVecr8R7rWeLKX1w1GM6NOV3hBVkjI%2BEMvfm5SCEWPJ%2F0kxg08%2Bz787%2F%2BvbbYUajZMKyA%2FERqMhSoI3wIfxZ4GUMU3XWzwPQxatb63Z%2BJVgzMS7Y81dTmuWGHtzkrk8aBQwxLD51QY6sgGTjgKn%2FNWm9xAJPFGzCQNiINbjOaITZUFH9uZi%2F3c7Pm9lGzmAQ3NbY2wEyMt3MqxrPQQ%2Btl3hLbYDI0iiPO%2BicaNwL4goi6HH06WDOKjdLEMnKfdohAt1gG9KQRHPZMFaPcv4FGvCv3K%2FTkU3iMPCgel63hh%2BCgARGWGeKvVzTCzWkj7JKCnbs8CvqSJcTsjqCH8r%2BQrZPIAUbtvReF1mc5HSeA4hyzDy0Oq9BDSRmHhp&amp;X-Amz-Algorithm=AWS4-HMAC-SHA256&amp;X-Amz-Credential=ASIAT7MQN47UT5SZP66E%2F20261001%2Feu-west-1%2Fs3%2Faws4_request&amp;X-Amz-Date=20261001T130752Z&amp;X-Amz-SignedHeaders=host&amp;X-Amz-Expires=900&amp;X-Amz-Signature=5dc806c2ec1eeb463776d75d86421fd9d64799ef0a9df6e74b14a061a765d5f1 300w\" sizes=\"(max-width: 610px) 100vw, 610px\" \/><\/li>\n<\/ul>\n<hr \/>\n<h1>Foreign Key<\/h1>\n<p>A foreign key connects each record in a table to a record in another table. The other table must be created before the tables can be linked.<br \/>\n<em>eg Each record in &#8220;appointments&#8221; table will link to a customer. The customers table must be created before the appointments table.<\/em><\/p>\n<ul>\n<li>Right-click on the Table that has the foreign key<\/li>\n<li>Select &#8220;Modify table&#8221;<br \/>\n<img decoding=\"async\" class=\"alignnone size-full wp-image-308\" src=\"https:\/\/blogs.glowscotland.org.uk\/sh\/public\/ahscomputingsql\/uploads\/sites\/3269\/2021\/03\/24125204\/DB4SQL-foreignkey-1.png\" alt=\"\" width=\"334\" height=\"160\" srcset=\"https:\/\/blogs.glowscotland.org.uk\/sh\/public\/ahscomputingsql\/uploads\/sites\/3269\/2021\/03\/24125204\/DB4SQL-foreignkey-1.png 334w, https:\/\/glow-prod-sh.s3.eu-west-1.amazonaws.com\/sh\/public\/ahscomputingsql\/uploads\/sites\/3269\/2021\/03\/24125204\/DB4SQL-foreignkey-1-300x144.png?X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&amp;X-Amz-Security-Token=IQoJb3JpZ2luX2VjELX%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCWV1LXdlc3QtMSJGMEQCIBJhAojVHJBWMswjNI7hwVeFC7xTPKkGPmapajJCNPrhAiB6QI3iuWz%2FA0gb6zTkrKhplCOB96oK%2BB%2BqWdRRay%2F6TCq5BQh%2BEAUaDDI3MzU3MDE5NTQzMyIM33cIKemvJ2eVvKnqKpYFgpIbp70DiwF5DxnMSFFmjW6ZiMJSc%2B3yuLO2RneTSG8d1sI7iZqIznKFCQ9MM2LLjKCbaJICtjDVmtUU3t7H2J8VbF0Itq%2Fa180Qb%2FQKdovgF6lGfJqTPVqf24JYmt52cu5OBCqFNtW%2B7ddBiY6oggGtbGq%2BQDhotdHK4RI%2Bt7Pbxy3na%2BeM3tzaxERW5UmmBsXfjo6z0kve8edHU0EWO6kA%2F1OqI8UznKNgoi%2Fo%2FqfK2XGwA7YoqEvAgil%2F5CBduVy06SoLw04iVdn9449z2ucXumvI67Dk05Bf%2Fc7tMlQ0S%2F7YKGH7hgfbntS8l%2F1Mwzdz7OQl6ryPp8LJUzBxiLfbEWqhblA1oz3Lp6qk%2FkRkozlOo%2FADYokL2Puziq4i9fHcCxtOL7SAvL7Wra%2F3sfxXMh8NJCBRClJkb%2F9fnt%2FGA%2BpkIHChGbfxR64bQkdDyVPswdZ7efhIoE5jEZNiQzXz2NKo8ELlHldxqrbGxkgEr%2FzfcdSddg3BCL3YV8gRPqNSvzEl08EiKT1DPuv8ggWym%2B4oeF3BvXML0FNjtu0dalqTJ8Gjl94bre3dj16rsfip1K3vxgXjxqZMVVbCSzcIw5O0OpFLXaWpFkqKN4OHaFjtLGJcQj%2Fz%2BOGHHMpaSSEVOhqMJjgJiKHBuVI5NTQ2xLniHvFmk%2FXpmuOvxNc0l%2FONyJs599c%2FtaSs2poGNu1qRUrtfQYQmVtEjgegWkN6PVFqPLz7gRHVhnIC%2FXnSkhabPnVecr8R7rWeLKX1w1GM6NOV3hBVkjI%2BEMvfm5SCEWPJ%2F0kxg08%2Bz787%2F%2BvbbYUajZMKyA%2FERqMhSoI3wIfxZ4GUMU3XWzwPQxatb63Z%2BJVgzMS7Y81dTmuWGHtzkrk8aBQwxLD51QY6sgGTjgKn%2FNWm9xAJPFGzCQNiINbjOaITZUFH9uZi%2F3c7Pm9lGzmAQ3NbY2wEyMt3MqxrPQQ%2Btl3hLbYDI0iiPO%2BicaNwL4goi6HH06WDOKjdLEMnKfdohAt1gG9KQRHPZMFaPcv4FGvCv3K%2FTkU3iMPCgel63hh%2BCgARGWGeKvVzTCzWkj7JKCnbs8CvqSJcTsjqCH8r%2BQrZPIAUbtvReF1mc5HSeA4hyzDy0Oq9BDSRmHhp&amp;X-Amz-Algorithm=AWS4-HMAC-SHA256&amp;X-Amz-Credential=ASIAT7MQN47UT5SZP66E%2F20261001%2Feu-west-1%2Fs3%2Faws4_request&amp;X-Amz-Date=20261001T130752Z&amp;X-Amz-SignedHeaders=host&amp;X-Amz-Expires=900&amp;X-Amz-Signature=27479f4224c18769c58befca664327ab2e8a0090b8b9bace1661287ca48fa8f1 300w\" sizes=\"(max-width: 334px) 100vw, 334px\" \/><\/li>\n<li>Widen the table so you can see the Foreign Key column<br \/>\n<img decoding=\"async\" class=\"alignnone size-full wp-image-307\" src=\"https:\/\/blogs.glowscotland.org.uk\/sh\/public\/ahscomputingsql\/uploads\/sites\/3269\/2021\/03\/24125203\/DB4SQL-foreignkey-2.png\" alt=\"\" width=\"497\" height=\"160\" srcset=\"https:\/\/blogs.glowscotland.org.uk\/sh\/public\/ahscomputingsql\/uploads\/sites\/3269\/2021\/03\/24125203\/DB4SQL-foreignkey-2.png 497w, https:\/\/glow-prod-sh.s3.eu-west-1.amazonaws.com\/sh\/public\/ahscomputingsql\/uploads\/sites\/3269\/2021\/03\/24125203\/DB4SQL-foreignkey-2-300x97.png?X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&amp;X-Amz-Security-Token=IQoJb3JpZ2luX2VjELX%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCWV1LXdlc3QtMSJGMEQCIBJhAojVHJBWMswjNI7hwVeFC7xTPKkGPmapajJCNPrhAiB6QI3iuWz%2FA0gb6zTkrKhplCOB96oK%2BB%2BqWdRRay%2F6TCq5BQh%2BEAUaDDI3MzU3MDE5NTQzMyIM33cIKemvJ2eVvKnqKpYFgpIbp70DiwF5DxnMSFFmjW6ZiMJSc%2B3yuLO2RneTSG8d1sI7iZqIznKFCQ9MM2LLjKCbaJICtjDVmtUU3t7H2J8VbF0Itq%2Fa180Qb%2FQKdovgF6lGfJqTPVqf24JYmt52cu5OBCqFNtW%2B7ddBiY6oggGtbGq%2BQDhotdHK4RI%2Bt7Pbxy3na%2BeM3tzaxERW5UmmBsXfjo6z0kve8edHU0EWO6kA%2F1OqI8UznKNgoi%2Fo%2FqfK2XGwA7YoqEvAgil%2F5CBduVy06SoLw04iVdn9449z2ucXumvI67Dk05Bf%2Fc7tMlQ0S%2F7YKGH7hgfbntS8l%2F1Mwzdz7OQl6ryPp8LJUzBxiLfbEWqhblA1oz3Lp6qk%2FkRkozlOo%2FADYokL2Puziq4i9fHcCxtOL7SAvL7Wra%2F3sfxXMh8NJCBRClJkb%2F9fnt%2FGA%2BpkIHChGbfxR64bQkdDyVPswdZ7efhIoE5jEZNiQzXz2NKo8ELlHldxqrbGxkgEr%2FzfcdSddg3BCL3YV8gRPqNSvzEl08EiKT1DPuv8ggWym%2B4oeF3BvXML0FNjtu0dalqTJ8Gjl94bre3dj16rsfip1K3vxgXjxqZMVVbCSzcIw5O0OpFLXaWpFkqKN4OHaFjtLGJcQj%2Fz%2BOGHHMpaSSEVOhqMJjgJiKHBuVI5NTQ2xLniHvFmk%2FXpmuOvxNc0l%2FONyJs599c%2FtaSs2poGNu1qRUrtfQYQmVtEjgegWkN6PVFqPLz7gRHVhnIC%2FXnSkhabPnVecr8R7rWeLKX1w1GM6NOV3hBVkjI%2BEMvfm5SCEWPJ%2F0kxg08%2Bz787%2F%2BvbbYUajZMKyA%2FERqMhSoI3wIfxZ4GUMU3XWzwPQxatb63Z%2BJVgzMS7Y81dTmuWGHtzkrk8aBQwxLD51QY6sgGTjgKn%2FNWm9xAJPFGzCQNiINbjOaITZUFH9uZi%2F3c7Pm9lGzmAQ3NbY2wEyMt3MqxrPQQ%2Btl3hLbYDI0iiPO%2BicaNwL4goi6HH06WDOKjdLEMnKfdohAt1gG9KQRHPZMFaPcv4FGvCv3K%2FTkU3iMPCgel63hh%2BCgARGWGeKvVzTCzWkj7JKCnbs8CvqSJcTsjqCH8r%2BQrZPIAUbtvReF1mc5HSeA4hyzDy0Oq9BDSRmHhp&amp;X-Amz-Algorithm=AWS4-HMAC-SHA256&amp;X-Amz-Credential=ASIAT7MQN47UT5SZP66E%2F20261001%2Feu-west-1%2Fs3%2Faws4_request&amp;X-Amz-Date=20261001T130752Z&amp;X-Amz-SignedHeaders=host&amp;X-Amz-Expires=900&amp;X-Amz-Signature=ae66655c8a70af390c7f2e8b54984668bc1811927a84c1f1982f606ad39a87fb 300w\" sizes=\"(max-width: 497px) 100vw, 497px\" \/><\/li>\n<\/ul>\n<ul>\n<li>Double-click where the foreign key row and the Foreign Key column cross:<br \/>\n<img decoding=\"async\" class=\"alignnone size-full wp-image-309\" src=\"https:\/\/blogs.glowscotland.org.uk\/sh\/public\/ahscomputingsql\/uploads\/sites\/3269\/2021\/03\/24125636\/DB4SQL-foreignkey-3.png\" alt=\"\" width=\"606\" height=\"83\" srcset=\"https:\/\/blogs.glowscotland.org.uk\/sh\/public\/ahscomputingsql\/uploads\/sites\/3269\/2021\/03\/24125636\/DB4SQL-foreignkey-3.png 606w, https:\/\/glow-prod-sh.s3.eu-west-1.amazonaws.com\/sh\/public\/ahscomputingsql\/uploads\/sites\/3269\/2021\/03\/24125636\/DB4SQL-foreignkey-3-300x41.png?X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&amp;X-Amz-Security-Token=IQoJb3JpZ2luX2VjELX%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCWV1LXdlc3QtMSJGMEQCIBJhAojVHJBWMswjNI7hwVeFC7xTPKkGPmapajJCNPrhAiB6QI3iuWz%2FA0gb6zTkrKhplCOB96oK%2BB%2BqWdRRay%2F6TCq5BQh%2BEAUaDDI3MzU3MDE5NTQzMyIM33cIKemvJ2eVvKnqKpYFgpIbp70DiwF5DxnMSFFmjW6ZiMJSc%2B3yuLO2RneTSG8d1sI7iZqIznKFCQ9MM2LLjKCbaJICtjDVmtUU3t7H2J8VbF0Itq%2Fa180Qb%2FQKdovgF6lGfJqTPVqf24JYmt52cu5OBCqFNtW%2B7ddBiY6oggGtbGq%2BQDhotdHK4RI%2Bt7Pbxy3na%2BeM3tzaxERW5UmmBsXfjo6z0kve8edHU0EWO6kA%2F1OqI8UznKNgoi%2Fo%2FqfK2XGwA7YoqEvAgil%2F5CBduVy06SoLw04iVdn9449z2ucXumvI67Dk05Bf%2Fc7tMlQ0S%2F7YKGH7hgfbntS8l%2F1Mwzdz7OQl6ryPp8LJUzBxiLfbEWqhblA1oz3Lp6qk%2FkRkozlOo%2FADYokL2Puziq4i9fHcCxtOL7SAvL7Wra%2F3sfxXMh8NJCBRClJkb%2F9fnt%2FGA%2BpkIHChGbfxR64bQkdDyVPswdZ7efhIoE5jEZNiQzXz2NKo8ELlHldxqrbGxkgEr%2FzfcdSddg3BCL3YV8gRPqNSvzEl08EiKT1DPuv8ggWym%2B4oeF3BvXML0FNjtu0dalqTJ8Gjl94bre3dj16rsfip1K3vxgXjxqZMVVbCSzcIw5O0OpFLXaWpFkqKN4OHaFjtLGJcQj%2Fz%2BOGHHMpaSSEVOhqMJjgJiKHBuVI5NTQ2xLniHvFmk%2FXpmuOvxNc0l%2FONyJs599c%2FtaSs2poGNu1qRUrtfQYQmVtEjgegWkN6PVFqPLz7gRHVhnIC%2FXnSkhabPnVecr8R7rWeLKX1w1GM6NOV3hBVkjI%2BEMvfm5SCEWPJ%2F0kxg08%2Bz787%2F%2BvbbYUajZMKyA%2FERqMhSoI3wIfxZ4GUMU3XWzwPQxatb63Z%2BJVgzMS7Y81dTmuWGHtzkrk8aBQwxLD51QY6sgGTjgKn%2FNWm9xAJPFGzCQNiINbjOaITZUFH9uZi%2F3c7Pm9lGzmAQ3NbY2wEyMt3MqxrPQQ%2Btl3hLbYDI0iiPO%2BicaNwL4goi6HH06WDOKjdLEMnKfdohAt1gG9KQRHPZMFaPcv4FGvCv3K%2FTkU3iMPCgel63hh%2BCgARGWGeKvVzTCzWkj7JKCnbs8CvqSJcTsjqCH8r%2BQrZPIAUbtvReF1mc5HSeA4hyzDy0Oq9BDSRmHhp&amp;X-Amz-Algorithm=AWS4-HMAC-SHA256&amp;X-Amz-Credential=ASIAT7MQN47UT5SZP66E%2F20261001%2Feu-west-1%2Fs3%2Faws4_request&amp;X-Amz-Date=20261001T130752Z&amp;X-Amz-SignedHeaders=host&amp;X-Amz-Expires=900&amp;X-Amz-Signature=8fbd33502663633a739d00f19fb0872ed33d53366466292788b8adf164b72b5f 300w\" sizes=\"(max-width: 606px) 100vw, 606px\" \/><\/li>\n<li>Use the drop-down menus to select the other table, and its primary key:<br \/>\n<img decoding=\"async\" class=\"alignnone size-full wp-image-310\" src=\"https:\/\/blogs.glowscotland.org.uk\/sh\/public\/ahscomputingsql\/uploads\/sites\/3269\/2021\/03\/24125850\/DB4SQL-foreignkey-4.png\" alt=\"\" width=\"607\" height=\"87\" srcset=\"https:\/\/blogs.glowscotland.org.uk\/sh\/public\/ahscomputingsql\/uploads\/sites\/3269\/2021\/03\/24125850\/DB4SQL-foreignkey-4.png 607w, https:\/\/glow-prod-sh.s3.eu-west-1.amazonaws.com\/sh\/public\/ahscomputingsql\/uploads\/sites\/3269\/2021\/03\/24125850\/DB4SQL-foreignkey-4-300x43.png?X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&amp;X-Amz-Security-Token=IQoJb3JpZ2luX2VjELX%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCWV1LXdlc3QtMSJGMEQCIBJhAojVHJBWMswjNI7hwVeFC7xTPKkGPmapajJCNPrhAiB6QI3iuWz%2FA0gb6zTkrKhplCOB96oK%2BB%2BqWdRRay%2F6TCq5BQh%2BEAUaDDI3MzU3MDE5NTQzMyIM33cIKemvJ2eVvKnqKpYFgpIbp70DiwF5DxnMSFFmjW6ZiMJSc%2B3yuLO2RneTSG8d1sI7iZqIznKFCQ9MM2LLjKCbaJICtjDVmtUU3t7H2J8VbF0Itq%2Fa180Qb%2FQKdovgF6lGfJqTPVqf24JYmt52cu5OBCqFNtW%2B7ddBiY6oggGtbGq%2BQDhotdHK4RI%2Bt7Pbxy3na%2BeM3tzaxERW5UmmBsXfjo6z0kve8edHU0EWO6kA%2F1OqI8UznKNgoi%2Fo%2FqfK2XGwA7YoqEvAgil%2F5CBduVy06SoLw04iVdn9449z2ucXumvI67Dk05Bf%2Fc7tMlQ0S%2F7YKGH7hgfbntS8l%2F1Mwzdz7OQl6ryPp8LJUzBxiLfbEWqhblA1oz3Lp6qk%2FkRkozlOo%2FADYokL2Puziq4i9fHcCxtOL7SAvL7Wra%2F3sfxXMh8NJCBRClJkb%2F9fnt%2FGA%2BpkIHChGbfxR64bQkdDyVPswdZ7efhIoE5jEZNiQzXz2NKo8ELlHldxqrbGxkgEr%2FzfcdSddg3BCL3YV8gRPqNSvzEl08EiKT1DPuv8ggWym%2B4oeF3BvXML0FNjtu0dalqTJ8Gjl94bre3dj16rsfip1K3vxgXjxqZMVVbCSzcIw5O0OpFLXaWpFkqKN4OHaFjtLGJcQj%2Fz%2BOGHHMpaSSEVOhqMJjgJiKHBuVI5NTQ2xLniHvFmk%2FXpmuOvxNc0l%2FONyJs599c%2FtaSs2poGNu1qRUrtfQYQmVtEjgegWkN6PVFqPLz7gRHVhnIC%2FXnSkhabPnVecr8R7rWeLKX1w1GM6NOV3hBVkjI%2BEMvfm5SCEWPJ%2F0kxg08%2Bz787%2F%2BvbbYUajZMKyA%2FERqMhSoI3wIfxZ4GUMU3XWzwPQxatb63Z%2BJVgzMS7Y81dTmuWGHtzkrk8aBQwxLD51QY6sgGTjgKn%2FNWm9xAJPFGzCQNiINbjOaITZUFH9uZi%2F3c7Pm9lGzmAQ3NbY2wEyMt3MqxrPQQ%2Btl3hLbYDI0iiPO%2BicaNwL4goi6HH06WDOKjdLEMnKfdohAt1gG9KQRHPZMFaPcv4FGvCv3K%2FTkU3iMPCgel63hh%2BCgARGWGeKvVzTCzWkj7JKCnbs8CvqSJcTsjqCH8r%2BQrZPIAUbtvReF1mc5HSeA4hyzDy0Oq9BDSRmHhp&amp;X-Amz-Algorithm=AWS4-HMAC-SHA256&amp;X-Amz-Credential=ASIAT7MQN47UT5SZP66E%2F20261001%2Feu-west-1%2Fs3%2Faws4_request&amp;X-Amz-Date=20261001T130752Z&amp;X-Amz-SignedHeaders=host&amp;X-Amz-Expires=900&amp;X-Amz-Signature=ead409b8544b588dcc7fab6fce9dcfdde3b265488a03d95d50f02398df6354fa 300w\" sizes=\"(max-width: 607px) 100vw, 607px\" \/><\/li>\n<li>Click inside the grey &#8220;Foreign key clauses&#8230;&#8221; box, and press the Enter key<\/li>\n<li>Check the code in the bottom panel, and press the OK button<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Level &#8211; National 5+ Primary Key Every table should have a primary key &#8211; a unique identifier for each record. Primary keys are required (Not Null), and\u00a0must be unique Right-click on the Table name Select &#8220;Modify table&#8221; Tick the NN, PK and U options for the primary key Foreign Key A foreign key connects each record in a table to a record in another table. The other table must be<\/p>\n<p><a class=\"more-link\" href=\"https:\/\/blogs.glowscotland.org.uk\/sh\/ahscomputingsql\/creating-a-database\/primary-key\/\">Read More<\/a><\/p>\n","protected":false},"author":7,"featured_media":0,"parent":262,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-195","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/blogs.glowscotland.org.uk\/sh\/ahscomputingsql\/wp-json\/wp\/v2\/pages\/195","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.glowscotland.org.uk\/sh\/ahscomputingsql\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/blogs.glowscotland.org.uk\/sh\/ahscomputingsql\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.glowscotland.org.uk\/sh\/ahscomputingsql\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.glowscotland.org.uk\/sh\/ahscomputingsql\/wp-json\/wp\/v2\/comments?post=195"}],"version-history":[{"count":10,"href":"https:\/\/blogs.glowscotland.org.uk\/sh\/ahscomputingsql\/wp-json\/wp\/v2\/pages\/195\/revisions"}],"predecessor-version":[{"id":407,"href":"https:\/\/blogs.glowscotland.org.uk\/sh\/ahscomputingsql\/wp-json\/wp\/v2\/pages\/195\/revisions\/407"}],"up":[{"embeddable":true,"href":"https:\/\/blogs.glowscotland.org.uk\/sh\/ahscomputingsql\/wp-json\/wp\/v2\/pages\/262"}],"wp:attachment":[{"href":"https:\/\/blogs.glowscotland.org.uk\/sh\/ahscomputingsql\/wp-json\/wp\/v2\/media?parent=195"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}