Refactor QueryBuilder usage and implement *char join pushdown in PostgreSQL

plugin/trino-base-jdbc/src/main/java/io/trino/plugin/jdbc/BaseJdbcClient.java

@@ -89,6 +89,7 @@ public abstract class BaseJdbcClient
     private static final Logger log = Logger.get(BaseJdbcClient.class);
 
     protected final ConnectionFactory connectionFactory;
+    protected final QueryBuilder queryBuilder;
     protected final String identifierQuote;
     protected final Set<String> jdbcTypesMappedToVarchar;
     private final IdentifierMapping identifierMapping;
@@ -97,23 +98,27 @@ public BaseJdbcClient(
             BaseJdbcConfig config,
             String identifierQuote,
             ConnectionFactory connectionFactory,
+            QueryBuilder queryBuilder,
             IdentifierMapping identifierMapping)
     {
         this(
                 identifierQuote,
                 connectionFactory,
+                queryBuilder,
                 config.getJdbcTypesMappedToVarchar(),
                 identifierMapping);
     }
 
     public BaseJdbcClient(
             String identifierQuote,
             ConnectionFactory connectionFactory,
+            QueryBuilder queryBuilder,
             Set<String> jdbcTypesMappedToVarchar,
             IdentifierMapping identifierMapping)
     {
         this.identifierQuote = requireNonNull(identifierQuote, "identifierQuote is null");
         this.connectionFactory = requireNonNull(connectionFactory, "connectionFactory is null");
+        this.queryBuilder = requireNonNull(queryBuilder, "queryBuilder is null");
         this.jdbcTypesMappedToVarchar = ImmutableSortedSet.orderedBy(CASE_INSENSITIVE_ORDER)
                 .addAll(requireNonNull(jdbcTypesMappedToVarchar, "jdbcTypesMappedToVarchar is null"))
                 .build();
@@ -377,7 +382,7 @@ public PreparedStatement buildSql(ConnectorSession session, Connection connectio
             throws SQLException
     {
         PreparedQuery preparedQuery = prepareQuery(session, connection, table, Optional.empty(), columns, ImmutableMap.of(), Optional.of(split));
-        return new QueryBuilder(this).prepareStatement(session, connection, preparedQuery);
+        return queryBuilder.prepareStatement(this, session, connection, preparedQuery);
     }
 
     protected PreparedQuery prepareQuery(
@@ -389,7 +394,8 @@ protected PreparedQuery prepareQuery(
             Map<String, String> columnExpressions,
             Optional<JdbcSplit> split)
     {
-        return applyQueryTransformations(table, new QueryBuilder(this).prepareQuery(
+        return applyQueryTransformations(table, queryBuilder.prepareSelectQuery(
+                this,
                 session,
                 connection,
                 table.getRelationHandle(),
@@ -412,23 +418,29 @@ public Optional<PreparedQuery> implementJoin(
             JoinStatistics statistics)
     {
         for (JdbcJoinCondition joinCondition : joinConditions) {
-            if (!isSupportedJoinCondition(joinCondition)) {
+            if (!isSupportedJoinCondition(session, joinCondition)) {
                 return Optional.empty();
             }
         }
 
-        QueryBuilder queryBuilder = new QueryBuilder(this);
-        return Optional.of(queryBuilder.prepareJoinQuery(
-                session,
-                joinType,
-                leftSource,
-                rightSource,
-                joinConditions,
-                leftAssignments,
-                rightAssignments));
+        try (Connection connection = this.connectionFactory.openConnection(session)) {
+            return Optional.of(queryBuilder.prepareJoinQuery(
+                    this,
+                    session,
+                    connection,
+                    joinType,
+                    leftSource,
+                    rightSource,
+                    joinConditions,
+                    leftAssignments,
+                    rightAssignments));
+        }
+        catch (SQLException e) {
+            throw new TrinoException(JDBC_ERROR, e);
+        }
     }
 
-    protected boolean isSupportedJoinCondition(JdbcJoinCondition joinCondition)
+    protected boolean isSupportedJoinCondition(ConnectorSession session, JdbcJoinCondition joinCondition)
     {
         return false;
     }
@@ -970,9 +982,8 @@ public OptionalLong delete(ConnectorSession session, JdbcTableHandle handle)
         checkArgument(handle.getSortOrder().isEmpty(), "Unable to delete when sort order is set: %s", handle);
         try (Connection connection = connectionFactory.openConnection(session)) {
             verify(connection.getAutoCommit());
-            QueryBuilder queryBuilder = new QueryBuilder(this);
-            PreparedQuery preparedQuery = queryBuilder.prepareDelete(session, connection, handle.getRequiredNamedRelation(), handle.getConstraint());
-            try (PreparedStatement preparedStatement = queryBuilder.prepareStatement(session, connection, preparedQuery)) {
+            PreparedQuery preparedQuery = queryBuilder.prepareDeleteQuery(this, session, connection, handle.getRequiredNamedRelation(), handle.getConstraint());
+            try (PreparedStatement preparedStatement = queryBuilder.prepareStatement(this, session, connection, preparedQuery)) {
                 return OptionalLong.of(preparedStatement.executeUpdate());
             }
         }