Bug Report: vtctldclient vdiff incorrectly limits rows

[mattlord]

Overview of the Issue

The new vtctldclient vdiff implementation (added in v18) incorrectly limits the maximum rows diffed per table to the max-extra-rows-to-compare flag value (default: 1000).

Reproduction Steps

git checkout main && make build

cd examples/local

./101_initial_cluster.sh; mysql < ../common/insert_commerce_data.sql; ./201_customer_tablets.sh; ./202_move_tables.sh

for i in {1..10}; do mysql commerce -e "insert into customer (email) values ('${RANDOM}_person_${RANDOM}@planetscale.com'); insert into customer (email) select email from customer;"; done

sleep 60

vtctldclient vdiff --target-keyspace customer --workflow commerce2customer create

sleep 10

vtctldclient vdiff --target-keyspace customer --workflow commerce2customer show last

command mysql -u root --socket=${VTDATAROOT}/vt_0000000201/mysql.sock -e "select * from _vt.vdiff\G"

If you look at the vdiff output you'll see that it only processed 1005 rows and if you look at vdiff record on the target side, you'll see that the max_rows core option is set to 1,000:

mysql> select * from _vt.vdiff\G
*************************** 1. row ***************************
                id: 1
        vdiff_uuid: 95741c3f-b465-429d-b770-ad54a4ed0ddb
          workflow: commerce2customer
          keyspace: customer
             shard: 0
           db_name: vt_customer
             state: completed
           options: {"core_options": {"max_rows": 1000, "auto_retry": true, "timeout_seconds": 30, "max_extra_rows_to_compare": 1000}, "picker_options": {"source_cell": "zone1", "target_cell": "zone1", "tablet_types": "in_order:rdonly,replica,primary"}, "report_options": {"max_sample_rows": 10}}
        created_at: 2023-12-13 14:10:04
        started_at: 2023-12-13 19:10:04
liveness_timestamp: NULL
      completed_at: 2023-12-13 19:10:04
        last_error:

Binary Version

vtgate version Version: 19.0.0-SNAPSHOT (Git revision 5ee1b9b735f09c54a19177c1d6dd2b08e0fad136 branch 'main') built on Wed Dec 13 15:26:40 EST 2023 by matt@pslord.local using go1.21.5 darwin/arm64

Operating System and Environment details

N/A

Log Fragments

No response

[deepthi]

Note: this affects v18 as well as main.