Merge pull request cockroachdb#62040 from postamar/backport21.1-62017

release-21.1: migration: add protected_ts_meta privilege migration

Merge pull request cockroachdb#61658 from RaduBerinde/backport20.2-61574

release-20.2: opt: detect invalid tuple comparison with ANY

Merge pull request cockroachdb#61423 from mgartner/backport20.1-61106

release-20.1: sql: disallow creation of interleaved partitioned indexes

changefeedccl: Apply avro schema prefix as a namespace

The avro_schema_prefix flag avoids collisions in the subject, but records or
lower-level fields could still collide. This PR sets the "namespace" property
on avro schemas to be equal to the prefix when provided.
Note that this slightly changes encoding: if the prefix "super" is provided,
"super." will be prepended to the keys of the subfields of an avro record,
such as the "after" part of an emitted value.

Release justification: low-risk update to behavior for a new flag
Release note (enterprise change): avro_schema_prefix flag sets Schema.namespace

Merge pull request cockroachdb#59703 from spaskob/managed-import

importccl: better error message for free-tier

Merge cockroachdb#59633

59633: multiregion: replace TODO and unimplemented with issue numbers r=ajstorm a=otan

In the spirit of Milestone planning, replace all remaining multiregion
TODOs with issue numbers.

Release note: None

Co-authored-by: Oliver Tan <otan@cockroachlabs.com>

tracing: revert trace.mode default to legacy

We are still seeing memory issues on tpccbench/nodes=6/cpu=16/multi-az
which need to be investigated. Turn off background tracing while we do.

Touches cockroachdb#58298. We're also reverting an earlier commit as part of this
one (d252400). This revert is needed given
we've not yet addressed an underlying bug (cockroachdb#59203).

Release note: None

Merge pull request cockroachdb#59272 from yuzefovich/backport20.1-59213

release-20.1: sql: fix ALTER INDEX ... SPLIT/UNSPLIT AT in error cases

Merge pull request cockroachdb#59172 from rytaft/backport20.1-59147

release-20.1: opt: fix bug where ON CONFLICT DO NOTHING ignores some input

Merge pull request cockroachdb#58720 from bdarnell/skippy-20.2