Make sure lookup vindexes are queryable inside transaction#6499
Merged
sougou merged 2 commits intovitessio:masterfrom Aug 2, 2020
Merged
Make sure lookup vindexes are queryable inside transaction#6499sougou merged 2 commits intovitessio:masterfrom
sougou merged 2 commits intovitessio:masterfrom
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Signed-off-by: Andres Taylor <andres@planetscale.com>
Signed-off-by: Andres Taylor <andres@planetscale.com>
sougou
approved these changes
Aug 2, 2020
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When adding data to tables that have consistent lookup vindexes defined on them, Vitess uses different connections to be able to commit data in discrete chunks - we
INSERTnew data to indexes before we add data to the base table. If something goes wrong along the way, it's acceptable to have data exist in the vindex that is not present in the base table - this will lead to unnecessary queries, but not inconsistent results.The issue this PR is solving is that we were not querying the lookup vindex on the correct connection while still inside the transaction, which leads to no data being found.
Note: for
DELETEd rows, we will query the vindex on the wrong connection, which will lead to unnecessary queries, butno wrong results, since the data has been deleted from the base table.