MySQL 5.7 (which was merged to MariaDB 10.2.2) implements an instantaneous change of the maximum length of a VARCHAR column when the length is increasing and not crossing the 255-byte boundary.
Alas, when the VARCHAR column was indexed, the indexes would be dropped and added. This should be avoided.
MySQL 5.7.23 addressed this by changing the storage engine API. We would prefer a less intrusive change. InnoDB should be able to ‘optimize away’ pairs of DROP INDEX and ADD INDEX operations. (While doing that, InnoDB in MariaDB should support the renaming of indexes as well, without introducing the RENAME INDEX syntax from MySQL 5.7.)
{"report":{"fcp":826.8000001907349,"ttfb":265.69999980926514,"pageVisibility":"visible","entityId":68921,"key":"jira.project.issue.view-issue","isInitial":true,"threshold":1000,"elementTimings":{},"userDeviceMemory":8,"userDeviceProcessors":64,"apdex":1,"journeyId":"d1d3942f-66de-4d1e-a4f5-126d44dc8c41","navigationType":0,"readyForUser":884.6000003814697,"redirectCount":0,"resourceLoadedEnd":410.80000019073486,"resourceLoadedStart":271.5,"resourceTiming":[{"duration":6.699999809265137,"initiatorType":"link","name":"https://jira.mariadb.org/s/2c21342762a6a02add1c328bed317ffd-CDN/lu2cib/820016/12ta74/0a8bac35585be7fc6c9cc5a0464cd4cf/_/download/contextbatch/css/_super/batch.css","startTime":271.5,"connectEnd":0,"connectStart":0,"domainLookupEnd":0,"domainLookupStart":0,"fetchStart":271.5,"redirectEnd":0,"redirectStart":0,"requestStart":0,"responseEnd":278.19999980926514,"responseStart":0,"secureConnectionStart":0},{"duration":6.59999942779541,"initiatorType":"link","name":"https://jira.mariadb.org/s/7ebd35e77e471bc30ff0eba799ebc151-CDN/lu2cib/820016/12ta74/494e4c556ecbb29f90a3d3b4f09cb99c/_/download/contextbatch/css/jira.browse.project,project.issue.navigator,jira.view.issue,jira.general,jira.global,atl.general,-_super/batch.css?agile_global_admin_condition=true&jag=true&jira.create.linked.issue=true&slack-enabled=true&whisper-enabled=true","startTime":271.80000019073486,"connectEnd":0,"connectStart":0,"domainLookupEnd":0,"domainLookupStart":0,"fetchStart":271.80000019073486,"redirectEnd":0,"redirectStart":0,"requestStart":0,"responseEnd":278.3999996185303,"responseStart":0,"secureConnectionStart":0},{"duration":78.69999980926514,"initiatorType":"script","name":"https://jira.mariadb.org/s/0917945aaa57108d00c5076fea35e069-CDN/lu2cib/820016/12ta74/0a8bac35585be7fc6c9cc5a0464cd4cf/_/download/contextbatch/js/_super/batch.js?locale=en","startTime":272,"connectEnd":272,"connectStart":272,"domainLookupEnd":272,"domainLookupStart":272,"fetchStart":272,"redirectEnd":0,"redirectStart":0,"requestStart":282.19999980926514,"responseEnd":350.69999980926514,"responseStart":294.8999996185303,"secureConnectionStart":272},{"duration":138.69999980926514,"initiatorType":"script","name":"https://jira.mariadb.org/s/2d8175ec2fa4c816e8023260bd8c1786-CDN/lu2cib/820016/12ta74/494e4c556ecbb29f90a3d3b4f09cb99c/_/download/contextbatch/js/jira.browse.project,project.issue.navigator,jira.view.issue,jira.general,jira.global,atl.general,-_super/batch.js?agile_global_admin_condition=true&jag=true&jira.create.linked.issue=true&locale=en&slack-enabled=true&whisper-enabled=true","startTime":272.1000003814697,"connectEnd":272.1000003814697,"connectStart":272.1000003814697,"domainLookupEnd":272.1000003814697,"domainLookupStart":272.1000003814697,"fetchStart":272.1000003814697,"redirectEnd":0,"redirectStart":0,"requestStart":282.80000019073486,"responseEnd":410.80000019073486,"responseStart":303.19999980926514,"secureConnectionStart":272.1000003814697},{"duration":36,"initiatorType":"script","name":"https://jira.mariadb.org/s/a9324d6758d385eb45c462685ad88f1d-CDN/lu2cib/820016/12ta74/c92c0caa9a024ae85b0ebdbed7fb4bd7/_/download/contextbatch/js/atl.global,-_super/batch.js?locale=en","startTime":272.30000019073486,"connectEnd":272.30000019073486,"connectStart":272.30000019073486,"domainLookupEnd":272.30000019073486,"domainLookupStart":272.30000019073486,"fetchStart":272.30000019073486,"redirectEnd":0,"redirectStart":0,"requestStart":284,"responseEnd":308.30000019073486,"responseStart":306.6000003814697,"secureConnectionStart":272.30000019073486},{"duration":53.5,"initiatorType":"script","name":"https://jira.mariadb.org/s/d41d8cd98f00b204e9800998ecf8427e-CDN/lu2cib/820016/12ta74/1.0/_/download/batch/jira.webresources:calendar-en/jira.webresources:calendar-en.js","startTime":272.3999996185303,"connectEnd":272.3999996185303,"connectStart":272.3999996185303,"domainLookupEnd":272.3999996185303,"domainLookupStart":272.3999996185303,"fetchStart":272.3999996185303,"redirectEnd":0,"redirectStart":0,"requestStart":285.1000003814697,"responseEnd":325.8999996185303,"responseStart":321.5,"secureConnectionStart":272.3999996185303},{"duration":48.79999923706055,"initiatorType":"script","name":"https://jira.mariadb.org/s/d41d8cd98f00b204e9800998ecf8427e-CDN/lu2cib/820016/12ta74/1.0/_/download/batch/jira.webresources:calendar-localisation-moment/jira.webresources:calendar-localisation-moment.js","startTime":272.6000003814697,"connectEnd":272.6000003814697,"connectStart":272.6000003814697,"domainLookupEnd":272.6000003814697,"domainLookupStart":272.6000003814697,"fetchStart":272.6000003814697,"redirectEnd":0,"redirectStart":0,"requestStart":286.5,"responseEnd":321.3999996185303,"responseStart":319.8999996185303,"secureConnectionStart":272.6000003814697},{"duration":13.300000190734863,"initiatorType":"link","name":"https://jira.mariadb.org/s/b04b06a02d1959df322d9cded3aeecc1-CDN/lu2cib/820016/12ta74/a2ff6aa845ffc9a1d22fe23d9ee791fc/_/download/contextbatch/css/jira.global.look-and-feel,-_super/batch.css","startTime":272.80000019073486,"connectEnd":0,"connectStart":0,"domainLookupEnd":0,"domainLookupStart":0,"fetchStart":272.80000019073486,"redirectEnd":0,"redirectStart":0,"requestStart":0,"responseEnd":286.1000003814697,"responseStart":0,"secureConnectionStart":0},{"duration":57.19999980926514,"initiatorType":"script","name":"https://jira.mariadb.org/rest/api/1.0/shortcuts/820016/47140b6e0a9bc2e4913da06536125810/shortcuts.js?context=issuenavigation&context=issueaction","startTime":273,"connectEnd":273,"connectStart":273,"domainLookupEnd":273,"domainLookupStart":273,"fetchStart":273,"redirectEnd":0,"redirectStart":0,"requestStart":288.19999980926514,"responseEnd":330.19999980926514,"responseStart":329.5,"secureConnectionStart":273},{"duration":14.59999942779541,"initiatorType":"link","name":"https://jira.mariadb.org/s/3ac36323ba5e4eb0af2aa7ac7211b4bb-CDN/lu2cib/820016/12ta74/d176f0986478cc64f24226b3d20c140d/_/download/contextbatch/css/com.atlassian.jira.projects.sidebar.init,-_super,-project.issue.navigator,-jira.view.issue/batch.css?jira.create.linked.issue=true","startTime":273.1000003814697,"connectEnd":0,"connectStart":0,"domainLookupEnd":0,"domainLookupStart":0,"fetchStart":273.1000003814697,"redirectEnd":0,"redirectStart":0,"requestStart":0,"responseEnd":287.69999980926514,"responseStart":0,"secureConnectionStart":0},{"duration":67.5,"initiatorType":"script","name":"https://jira.mariadb.org/s/5d5e8fe91fbc506585e83ea3b62ccc4b-CDN/lu2cib/820016/12ta74/d176f0986478cc64f24226b3d20c140d/_/download/contextbatch/js/com.atlassian.jira.projects.sidebar.init,-_super,-project.issue.navigator,-jira.view.issue/batch.js?jira.create.linked.issue=true&locale=en","startTime":273.3999996185303,"connectEnd":273.3999996185303,"connectStart":273.3999996185303,"domainLookupEnd":273.3999996185303,"domainLookupStart":273.3999996185303,"fetchStart":273.3999996185303,"redirectEnd":0,"redirectStart":0,"requestStart":293.6000003814697,"responseEnd":340.8999996185303,"responseStart":338.69999980926514,"secureConnectionStart":273.3999996185303},{"duration":33.19999980926514,"initiatorType":"script","name":"https://jira.mariadb.org/s/d41d8cd98f00b204e9800998ecf8427e-CDN/lu2cib/820016/12ta74/1.0/_/download/batch/jira.webresources:bigpipe-js/jira.webresources:bigpipe-js.js","startTime":282.6000003814697,"connectEnd":301.19999980926514,"connectStart":301.19999980926514,"domainLookupEnd":301.19999980926514,"domainLookupStart":301.19999980926514,"fetchStart":282.6000003814697,"redirectEnd":0,"redirectStart":0,"requestStart":302.30000019073486,"responseEnd":315.80000019073486,"responseStart":313.5,"secureConnectionStart":301.19999980926514},{"duration":35.79999923706055,"initiatorType":"script","name":"https://jira.mariadb.org/s/d41d8cd98f00b204e9800998ecf8427e-CDN/lu2cib/820016/12ta74/1.0/_/download/batch/jira.webresources:bigpipe-init/jira.webresources:bigpipe-init.js","startTime":283.6000003814697,"connectEnd":283.6000003814697,"connectStart":283.6000003814697,"domainLookupEnd":283.6000003814697,"domainLookupStart":283.6000003814697,"fetchStart":283.6000003814697,"redirectEnd":0,"redirectStart":0,"requestStart":303,"responseEnd":319.3999996185303,"responseStart":316,"secureConnectionStart":283.6000003814697},{"duration":167.10000038146973,"initiatorType":"xmlhttprequest","name":"https://jira.mariadb.org/rest/webResources/1.0/resources","startTime":569.6999998092651,"connectEnd":569.6999998092651,"connectStart":569.6999998092651,"domainLookupEnd":569.6999998092651,"domainLookupStart":569.6999998092651,"fetchStart":569.6999998092651,"redirectEnd":0,"redirectStart":0,"requestStart":697.3000001907349,"responseEnd":736.8000001907349,"responseStart":734,"secureConnectionStart":569.6999998092651}],"fetchStart":0,"domainLookupStart":0,"domainLookupEnd":0,"connectStart":0,"connectEnd":0,"requestStart":97,"responseStart":265,"responseEnd":283,"domLoading":269,"domInteractive":944,"domContentLoadedEventStart":944,"domContentLoadedEventEnd":982,"domComplete":1653,"loadEventStart":1653,"loadEventEnd":1654,"userAgent":"Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)","marks":[{"name":"bigPipe.sidebar-id.start","time":920.1999998092651},{"name":"bigPipe.sidebar-id.end","time":920.8999996185303},{"name":"bigPipe.activity-panel-pipe-id.start","time":921.1000003814697},{"name":"bigPipe.activity-panel-pipe-id.end","time":922.8000001907349},{"name":"activityTabFullyLoaded","time":999.6000003814697}],"measures":[],"correlationId":"ba91f3f621211a","effectiveType":"4g","downlink":10,"rtt":0,"serverDuration":108,"dbReadsTimeInMs":15,"dbConnsTimeInMs":25,"applicationHash":"9d11dbea5f4be3d4cc21f03a88dd11d8c8687422","experiments":[]}}
While implementing this, please see if in ROW_FORMAT=REDUNDANT, we can also extend VARCHAR from any size to any size. The limitation regarding the 255-byte maximum length only applies to other ROW_FORMAT.