{"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=IQoJb3JpZ2luX2VjEL%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCWV1LXdlc3QtMSJHMEUCIFo53gvkmoSu7DzO3pGN9ew%2Fs47vjGwUQTzwGUInezhtAiEAt2m%2FPggQrbW1xYS9TX5ZcpaanoBIjKO6fzdCQNmgVckqwQUIiP%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARAFGgwyNzM1NzAxOTU0MzMiDEJeQe8tHfMVsAhJGSqVBbvsZWm6pB4mOw81hp2MSXO8fGq4MulOqdYINv1Gb34Srh9KWEBWW89igsk%2F%2FifQu7BE9nA%2Fycy4mSvCDbFem8GEyujroO9bhC2jzKBi6rWT7CWQTmDxlurP3kMFqoAAS7LLptiS4fSTUpbLKF2XR54bk1WrYvwQ9YXCECWWzE0%2F422kevpzrfZNOjOxIqB9oD9KHC7f2z9KKwX%2FtWKXateBsT%2FYVUo%2F95Dt15JGUOXS6wZWNEGJ06bR%2FHOyVHI2sTUf6uVSOdVEnskNXGQF6DJGrW%2FoU2y%2BAhTgkOCeLmsjvf9PobA9kqseYXRoGrRpGZNhiv6lVM00A8bopVD3q5S2xDHRJ9hOruLfrpUP34%2FsBFnehRc%2FgKMc7aQp5nbYryvXWyywmXeaYA3ad68x%2Fs5Ve3g4D%2FoaNmh7UlAIg2DuobuXfK9uFsANaTYl6DJ1XfZBmlpf5xiMKCRR0J2tLu%2BZaa1eFBcBpc4VE2qZ3qQumpNvvrGoV43SZAPJWqFO5MieJY1YgHfFZEUmLOZ2Kb32UhkbdYmw0fxsWmSFsxKCv86tR7mlSc%2FmVQIlTgTF5GEV0AMUv3FiMLrWB3m17e6h6%2BpeHX8K22kbXHHpzt%2Fef2NcXyJIlEOwYREsd4kS%2BKsS68PgMG8A1SJtTV6g08Up9UA7YFd59rqI3%2BA%2F9rAvgoWgrIqewGGNLCilj1m9mgO028DTySzSA%2FMKd1elfu%2Bdyl6ybh58aQo2HdcMy2kwCUCNLxLuv%2FSyy6Qawid2SNcyAL8rE5BmO%2BpadrgUX8YG0PpbkzPBrXvK5T3%2ByIxss53Hcg7gSpLtEz%2BjxO2xzLywH7DAZ1DM1qvr0wnMv5qInjjBxeCwOpp%2FBydWH%2Fb%2FUND9Q98w4%2F6K1QY6sQGhUrvKRV253QpP%2B09KOqOUUqyyWocbygpneQcTUB7X6O93WLwSTwXLzxA2HEYIQZb9UeogiVRXoYEWSiDX3BBbE2TgwS4CB8VRMglxGfGmjlE%2BynNNMyhefIp1VBKjBheOPCxVqJCaGUUoumDcHNMu9AFE9MQb8bPxJP2oym67j3hf0E0t%2FPgWeQ0EwtH2GCTvXxfcs8N%2BitBKnPloRTEdbJ%2Bvw8Z1IjBC8K%2BBMreu8d4%3D&amp;X-Amz-Algorithm=AWS4-HMAC-SHA256&amp;X-Amz-Credential=ASIAT7MQN47U5NL2N2D6%2F20260910%2Feu-west-1%2Fs3%2Faws4_request&amp;X-Amz-Date=20260910T143615Z&amp;X-Amz-SignedHeaders=host&amp;X-Amz-Expires=899&amp;X-Amz-Signature=77ee9230b5cfcb4dcdddebf84e81495b8825a147eba9989149cbb7b3f908fab6 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=IQoJb3JpZ2luX2VjEL%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCWV1LXdlc3QtMSJHMEUCIFo53gvkmoSu7DzO3pGN9ew%2Fs47vjGwUQTzwGUInezhtAiEAt2m%2FPggQrbW1xYS9TX5ZcpaanoBIjKO6fzdCQNmgVckqwQUIiP%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARAFGgwyNzM1NzAxOTU0MzMiDEJeQe8tHfMVsAhJGSqVBbvsZWm6pB4mOw81hp2MSXO8fGq4MulOqdYINv1Gb34Srh9KWEBWW89igsk%2F%2FifQu7BE9nA%2Fycy4mSvCDbFem8GEyujroO9bhC2jzKBi6rWT7CWQTmDxlurP3kMFqoAAS7LLptiS4fSTUpbLKF2XR54bk1WrYvwQ9YXCECWWzE0%2F422kevpzrfZNOjOxIqB9oD9KHC7f2z9KKwX%2FtWKXateBsT%2FYVUo%2F95Dt15JGUOXS6wZWNEGJ06bR%2FHOyVHI2sTUf6uVSOdVEnskNXGQF6DJGrW%2FoU2y%2BAhTgkOCeLmsjvf9PobA9kqseYXRoGrRpGZNhiv6lVM00A8bopVD3q5S2xDHRJ9hOruLfrpUP34%2FsBFnehRc%2FgKMc7aQp5nbYryvXWyywmXeaYA3ad68x%2Fs5Ve3g4D%2FoaNmh7UlAIg2DuobuXfK9uFsANaTYl6DJ1XfZBmlpf5xiMKCRR0J2tLu%2BZaa1eFBcBpc4VE2qZ3qQumpNvvrGoV43SZAPJWqFO5MieJY1YgHfFZEUmLOZ2Kb32UhkbdYmw0fxsWmSFsxKCv86tR7mlSc%2FmVQIlTgTF5GEV0AMUv3FiMLrWB3m17e6h6%2BpeHX8K22kbXHHpzt%2Fef2NcXyJIlEOwYREsd4kS%2BKsS68PgMG8A1SJtTV6g08Up9UA7YFd59rqI3%2BA%2F9rAvgoWgrIqewGGNLCilj1m9mgO028DTySzSA%2FMKd1elfu%2Bdyl6ybh58aQo2HdcMy2kwCUCNLxLuv%2FSyy6Qawid2SNcyAL8rE5BmO%2BpadrgUX8YG0PpbkzPBrXvK5T3%2ByIxss53Hcg7gSpLtEz%2BjxO2xzLywH7DAZ1DM1qvr0wnMv5qInjjBxeCwOpp%2FBydWH%2Fb%2FUND9Q98w4%2F6K1QY6sQGhUrvKRV253QpP%2B09KOqOUUqyyWocbygpneQcTUB7X6O93WLwSTwXLzxA2HEYIQZb9UeogiVRXoYEWSiDX3BBbE2TgwS4CB8VRMglxGfGmjlE%2BynNNMyhefIp1VBKjBheOPCxVqJCaGUUoumDcHNMu9AFE9MQb8bPxJP2oym67j3hf0E0t%2FPgWeQ0EwtH2GCTvXxfcs8N%2BitBKnPloRTEdbJ%2Bvw8Z1IjBC8K%2BBMreu8d4%3D&amp;X-Amz-Algorithm=AWS4-HMAC-SHA256&amp;X-Amz-Credential=ASIAT7MQN47U5NL2N2D6%2F20260910%2Feu-west-1%2Fs3%2Faws4_request&amp;X-Amz-Date=20260910T143615Z&amp;X-Amz-SignedHeaders=host&amp;X-Amz-Expires=900&amp;X-Amz-Signature=4e19033193f8a66e180febc34d12afc9673231667aa15cb16471a00bb5cf9425 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=IQoJb3JpZ2luX2VjEL%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCWV1LXdlc3QtMSJHMEUCIFo53gvkmoSu7DzO3pGN9ew%2Fs47vjGwUQTzwGUInezhtAiEAt2m%2FPggQrbW1xYS9TX5ZcpaanoBIjKO6fzdCQNmgVckqwQUIiP%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARAFGgwyNzM1NzAxOTU0MzMiDEJeQe8tHfMVsAhJGSqVBbvsZWm6pB4mOw81hp2MSXO8fGq4MulOqdYINv1Gb34Srh9KWEBWW89igsk%2F%2FifQu7BE9nA%2Fycy4mSvCDbFem8GEyujroO9bhC2jzKBi6rWT7CWQTmDxlurP3kMFqoAAS7LLptiS4fSTUpbLKF2XR54bk1WrYvwQ9YXCECWWzE0%2F422kevpzrfZNOjOxIqB9oD9KHC7f2z9KKwX%2FtWKXateBsT%2FYVUo%2F95Dt15JGUOXS6wZWNEGJ06bR%2FHOyVHI2sTUf6uVSOdVEnskNXGQF6DJGrW%2FoU2y%2BAhTgkOCeLmsjvf9PobA9kqseYXRoGrRpGZNhiv6lVM00A8bopVD3q5S2xDHRJ9hOruLfrpUP34%2FsBFnehRc%2FgKMc7aQp5nbYryvXWyywmXeaYA3ad68x%2Fs5Ve3g4D%2FoaNmh7UlAIg2DuobuXfK9uFsANaTYl6DJ1XfZBmlpf5xiMKCRR0J2tLu%2BZaa1eFBcBpc4VE2qZ3qQumpNvvrGoV43SZAPJWqFO5MieJY1YgHfFZEUmLOZ2Kb32UhkbdYmw0fxsWmSFsxKCv86tR7mlSc%2FmVQIlTgTF5GEV0AMUv3FiMLrWB3m17e6h6%2BpeHX8K22kbXHHpzt%2Fef2NcXyJIlEOwYREsd4kS%2BKsS68PgMG8A1SJtTV6g08Up9UA7YFd59rqI3%2BA%2F9rAvgoWgrIqewGGNLCilj1m9mgO028DTySzSA%2FMKd1elfu%2Bdyl6ybh58aQo2HdcMy2kwCUCNLxLuv%2FSyy6Qawid2SNcyAL8rE5BmO%2BpadrgUX8YG0PpbkzPBrXvK5T3%2ByIxss53Hcg7gSpLtEz%2BjxO2xzLywH7DAZ1DM1qvr0wnMv5qInjjBxeCwOpp%2FBydWH%2Fb%2FUND9Q98w4%2F6K1QY6sQGhUrvKRV253QpP%2B09KOqOUUqyyWocbygpneQcTUB7X6O93WLwSTwXLzxA2HEYIQZb9UeogiVRXoYEWSiDX3BBbE2TgwS4CB8VRMglxGfGmjlE%2BynNNMyhefIp1VBKjBheOPCxVqJCaGUUoumDcHNMu9AFE9MQb8bPxJP2oym67j3hf0E0t%2FPgWeQ0EwtH2GCTvXxfcs8N%2BitBKnPloRTEdbJ%2Bvw8Z1IjBC8K%2BBMreu8d4%3D&amp;X-Amz-Algorithm=AWS4-HMAC-SHA256&amp;X-Amz-Credential=ASIAT7MQN47U5NL2N2D6%2F20260910%2Feu-west-1%2Fs3%2Faws4_request&amp;X-Amz-Date=20260910T143615Z&amp;X-Amz-SignedHeaders=host&amp;X-Amz-Expires=900&amp;X-Amz-Signature=530bb021f46e61919ce032d55275abc207c033605fe7b817f12d52d879e907e9 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=IQoJb3JpZ2luX2VjEL%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCWV1LXdlc3QtMSJHMEUCIFo53gvkmoSu7DzO3pGN9ew%2Fs47vjGwUQTzwGUInezhtAiEAt2m%2FPggQrbW1xYS9TX5ZcpaanoBIjKO6fzdCQNmgVckqwQUIiP%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARAFGgwyNzM1NzAxOTU0MzMiDEJeQe8tHfMVsAhJGSqVBbvsZWm6pB4mOw81hp2MSXO8fGq4MulOqdYINv1Gb34Srh9KWEBWW89igsk%2F%2FifQu7BE9nA%2Fycy4mSvCDbFem8GEyujroO9bhC2jzKBi6rWT7CWQTmDxlurP3kMFqoAAS7LLptiS4fSTUpbLKF2XR54bk1WrYvwQ9YXCECWWzE0%2F422kevpzrfZNOjOxIqB9oD9KHC7f2z9KKwX%2FtWKXateBsT%2FYVUo%2F95Dt15JGUOXS6wZWNEGJ06bR%2FHOyVHI2sTUf6uVSOdVEnskNXGQF6DJGrW%2FoU2y%2BAhTgkOCeLmsjvf9PobA9kqseYXRoGrRpGZNhiv6lVM00A8bopVD3q5S2xDHRJ9hOruLfrpUP34%2FsBFnehRc%2FgKMc7aQp5nbYryvXWyywmXeaYA3ad68x%2Fs5Ve3g4D%2FoaNmh7UlAIg2DuobuXfK9uFsANaTYl6DJ1XfZBmlpf5xiMKCRR0J2tLu%2BZaa1eFBcBpc4VE2qZ3qQumpNvvrGoV43SZAPJWqFO5MieJY1YgHfFZEUmLOZ2Kb32UhkbdYmw0fxsWmSFsxKCv86tR7mlSc%2FmVQIlTgTF5GEV0AMUv3FiMLrWB3m17e6h6%2BpeHX8K22kbXHHpzt%2Fef2NcXyJIlEOwYREsd4kS%2BKsS68PgMG8A1SJtTV6g08Up9UA7YFd59rqI3%2BA%2F9rAvgoWgrIqewGGNLCilj1m9mgO028DTySzSA%2FMKd1elfu%2Bdyl6ybh58aQo2HdcMy2kwCUCNLxLuv%2FSyy6Qawid2SNcyAL8rE5BmO%2BpadrgUX8YG0PpbkzPBrXvK5T3%2ByIxss53Hcg7gSpLtEz%2BjxO2xzLywH7DAZ1DM1qvr0wnMv5qInjjBxeCwOpp%2FBydWH%2Fb%2FUND9Q98w4%2F6K1QY6sQGhUrvKRV253QpP%2B09KOqOUUqyyWocbygpneQcTUB7X6O93WLwSTwXLzxA2HEYIQZb9UeogiVRXoYEWSiDX3BBbE2TgwS4CB8VRMglxGfGmjlE%2BynNNMyhefIp1VBKjBheOPCxVqJCaGUUoumDcHNMu9AFE9MQb8bPxJP2oym67j3hf0E0t%2FPgWeQ0EwtH2GCTvXxfcs8N%2BitBKnPloRTEdbJ%2Bvw8Z1IjBC8K%2BBMreu8d4%3D&amp;X-Amz-Algorithm=AWS4-HMAC-SHA256&amp;X-Amz-Credential=ASIAT7MQN47U5NL2N2D6%2F20260910%2Feu-west-1%2Fs3%2Faws4_request&amp;X-Amz-Date=20260910T143615Z&amp;X-Amz-SignedHeaders=host&amp;X-Amz-Expires=900&amp;X-Amz-Signature=11816df19260753b6e45f86d16a35b97334fe5d4fb445702acec3b8e1d6f5acc 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=IQoJb3JpZ2luX2VjEL%2F%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FwEaCWV1LXdlc3QtMSJHMEUCIFo53gvkmoSu7DzO3pGN9ew%2Fs47vjGwUQTzwGUInezhtAiEAt2m%2FPggQrbW1xYS9TX5ZcpaanoBIjKO6fzdCQNmgVckqwQUIiP%2F%2F%2F%2F%2F%2F%2F%2F%2F%2FARAFGgwyNzM1NzAxOTU0MzMiDEJeQe8tHfMVsAhJGSqVBbvsZWm6pB4mOw81hp2MSXO8fGq4MulOqdYINv1Gb34Srh9KWEBWW89igsk%2F%2FifQu7BE9nA%2Fycy4mSvCDbFem8GEyujroO9bhC2jzKBi6rWT7CWQTmDxlurP3kMFqoAAS7LLptiS4fSTUpbLKF2XR54bk1WrYvwQ9YXCECWWzE0%2F422kevpzrfZNOjOxIqB9oD9KHC7f2z9KKwX%2FtWKXateBsT%2FYVUo%2F95Dt15JGUOXS6wZWNEGJ06bR%2FHOyVHI2sTUf6uVSOdVEnskNXGQF6DJGrW%2FoU2y%2BAhTgkOCeLmsjvf9PobA9kqseYXRoGrRpGZNhiv6lVM00A8bopVD3q5S2xDHRJ9hOruLfrpUP34%2FsBFnehRc%2FgKMc7aQp5nbYryvXWyywmXeaYA3ad68x%2Fs5Ve3g4D%2FoaNmh7UlAIg2DuobuXfK9uFsANaTYl6DJ1XfZBmlpf5xiMKCRR0J2tLu%2BZaa1eFBcBpc4VE2qZ3qQumpNvvrGoV43SZAPJWqFO5MieJY1YgHfFZEUmLOZ2Kb32UhkbdYmw0fxsWmSFsxKCv86tR7mlSc%2FmVQIlTgTF5GEV0AMUv3FiMLrWB3m17e6h6%2BpeHX8K22kbXHHpzt%2Fef2NcXyJIlEOwYREsd4kS%2BKsS68PgMG8A1SJtTV6g08Up9UA7YFd59rqI3%2BA%2F9rAvgoWgrIqewGGNLCilj1m9mgO028DTySzSA%2FMKd1elfu%2Bdyl6ybh58aQo2HdcMy2kwCUCNLxLuv%2FSyy6Qawid2SNcyAL8rE5BmO%2BpadrgUX8YG0PpbkzPBrXvK5T3%2ByIxss53Hcg7gSpLtEz%2BjxO2xzLywH7DAZ1DM1qvr0wnMv5qInjjBxeCwOpp%2FBydWH%2Fb%2FUND9Q98w4%2F6K1QY6sQGhUrvKRV253QpP%2B09KOqOUUqyyWocbygpneQcTUB7X6O93WLwSTwXLzxA2HEYIQZb9UeogiVRXoYEWSiDX3BBbE2TgwS4CB8VRMglxGfGmjlE%2BynNNMyhefIp1VBKjBheOPCxVqJCaGUUoumDcHNMu9AFE9MQb8bPxJP2oym67j3hf0E0t%2FPgWeQ0EwtH2GCTvXxfcs8N%2BitBKnPloRTEdbJ%2Bvw8Z1IjBC8K%2BBMreu8d4%3D&amp;X-Amz-Algorithm=AWS4-HMAC-SHA256&amp;X-Amz-Credential=ASIAT7MQN47U5NL2N2D6%2F20260910%2Feu-west-1%2Fs3%2Faws4_request&amp;X-Amz-Date=20260910T143615Z&amp;X-Amz-SignedHeaders=host&amp;X-Amz-Expires=900&amp;X-Amz-Signature=2cbfdc161a1eabecf62b9c90f546ab7ed01bffcc952dfcf1c31192c1c0501cf8 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}]}}