. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 How do I choose between master vs. replica for queries? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 There . . . . . . . 203 Elevated query latency on master . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203 Master starts up read-only . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204 Vitess sees the wrong tablet as master . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204 User Guides

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 How do I choose between master vs. replica for queries? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 There . . . . . . . 175 Elevated query latency on master . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176 Master starts up read-only . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176 Vitess sees the wrong tablet as master . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176 User Guides

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 How do I choose between master vs. replica for queries? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 There . . . . . . . 167 Elevated query latency on master . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167 Master starts up read-only . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167 Vitess sees the wrong tablet as master . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168 User Guides

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 How do I choose between master vs. replica for queries? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 There . . . . . . . 224 Elevated query latency on master . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224 Master starts up read-only . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225 Vitess sees the wrong tablet as master . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225 User Guides

306 Elevated query latency on master . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306 Elevated query latency on master . . . . . . . . . . . . . . . . . . . . . . . . . . . 306 Master starts up read-only . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307 Master starts up read-only . . . . Vitess sees the wrong tablet as master . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307 Vitess sees the wrong tablet as master . . . . . . . . . . . . . . .

264 Elevated query latency on master . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265 Elevated query latency on master . . . . . . . . . . . . . . . . . . . . . . . . . . . 265 Master starts up read-only . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265 Master starts up read-only . . . . Vitess sees the wrong tablet as master . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265 Vitess sees the wrong tablet as master . . . . . . . . . . . . . . .

284 Elevated query latency on master . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 284 Elevated query latency on master . . . . . . . . . . . . . . . . . . . . . . . . . . . 284 Master starts up read-only . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285 Master starts up read-only . . . . Vitess sees the wrong tablet as master . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285 Vitess sees the wrong tablet as master . . . . . . . . . . . . . . .

tree-like structure, which represents the overall execution plan. The plan represents each operator as a node in the tree. Each operator takes as input zero or more rows, and produces as output zero or more rows Topology Service, and in some cases are also able to evaluate expression values locally. Each leaf node will not have input from other operators, and pipe in any nodes they produce into their parent nodes The parents nodes will then pipe in nodes to their parent nodes, all the way up to a root node. The root node produces the final results of the query and delivers the results to the user. Observing Execution

public. The Vitess maintainers will fix issues upstream, and OSS-Fuzz will pull the latest Vitess master branch the next time it performs a fuzz run and verify that a given issue has been fixed. Vitess's error: HttpResponseNotOkError: [status 500] /api/keyspaces: unknown rpc error: code = Unknown desc = node doesn't exist: /vitess/global/keyspaces/KEYSPACE_NAME/Keyspace If a single keyspace returns an error

downtime Vitess Resharding • shard0, shard1, origin master —> vttablet • prepare two spare shard0, shard1 • vtgate point to origin master • multi-snapshot : data & repl-pos • multi-restore shard1 read-only. • shard0, shard1 replication to orign master • set origin master read-only • wait until shard0, shard1 catch origin master. • update configure server, vtgate point to shard0, shard1 vtgate [a-z] [a-m] [n-z] Vitess Snapshot • prepare • set read-only • stop slave • get master position & slave position. • flush tables with read lock • select {.keyspaceIdColumnName}, {