postgres: Add replication support for tsvector

This CL "allows" snapshot/replication to occur for postgres `tsvector`
types, but we intentionally throw away the data (and store NULL). This
is because Readyset has no intention of supporting `tsvector` data
types as they will never be a good candidate for caching, at least not
for a very long time.

Discarding the data allows us to import the rest of the table's data,
which can be used for proper cached queries in Readyset.

Fixes: REA-5734
Release-Note-Core: Support replication of postgres `tsvector` data
  types. Readyset interntionally discards the data as we will not
  support tsvector queries in the product.
Change-Id: I28f209a96939f1cc58fd616b5cd5e07d8c0ddb23
Reviewed-on: https://gerrit.readyset.name/c/readyset/+/9511
Tested-by: Buildkite CI
Reviewed-by: Michael Zink <michael.z@readyset.io>

Author: jasobrown-rs

logictests/replicated/psql/tsvector.test

@@ -0,0 +1,28 @@
+statement ok
+create table documents (id int primary key, content_vector tsvector);
+
+statement ok
+insert into documents values
+  (1, to_tsvector('english', 'The quick brown fox jumps over the lazy dog'));
+
+sleep 1000
+
+query T nosort
+select content_vector from documents where id = 1
+----
+NULL
+
+statement ok
+update documents values set content_vector = to_tsvector('english', 'A fast white rabbit jumps over the fence') where id = 1;
+
+sleep 1000
+
+query T nosort
+select content_vector from documents where id = 1
+----
+NULL
+
+
+
+
+

readyset-data/src/lib.rs

@@ -2205,6 +2205,8 @@ impl<'a> FromSql<'a> for DfValue {
                     Ok(DfValue::from(out))
                 }
                 Type::BIT | Type::VARBIT => mk_from_sql!(BitVec),
+                // we intentionally throw away the tsvector data.
+                Type::TS_VECTOR => Ok(DfValue::None),
                 ref ty if ty.name() == "citext" => Ok(DfValue::from_str_and_collation(
                     <&str>::from_sql(ty, raw)?,
                     Collation::Citext,

replicators/src/postgres_connector/wal_reader.rs

@@ -627,6 +627,7 @@ impl wal::TupleData {
                                     PGType::UUID => DfType::Uuid,
                                     PGType::BIT => DfType::DEFAULT_BIT,
                                     PGType::VARBIT => DfType::VarBit(None),
+                                    PGType::TS_VECTOR => DfType::Tsvector,
                                     ref ty => {
                                         trace!("got unsupported type '{}'", ty.to_string());
                                         return Err(unsupported_type_err());
@@ -847,6 +848,8 @@ impl wal::TupleData {
                                     }
                                     DfValue::from(bits)
                                 }
+                                // we intentionally throw away the tsvector data.
+                                PGType::TS_VECTOR => DfValue::None,
                                 _ => return Err(unsupported_type_err()),
                             },
                         }