class Insert

class Insert extends QueryInsert {
    public function execute() {
        if (!$this->preExecute()) {
            return NULL;
        }
        $stmt = $this->connection
            ->prepareStatement((string) $this, $this->queryOptions);
        // Fetch the list of blobs and sequences used on that table.
        $table_information = $this->connection
            ->schema()
            ->queryTableInformation($this->table);
        $max_placeholder = 0;
        $blobs = [];
        $blob_count = 0;
        foreach ($this->insertValues as $insert_values) {
            foreach ($this->insertFields as $idx => $field) {
                if (isset($table_information->blob_fields[$field]) && $insert_values[$idx] !== NULL) {
                    $blobs[$blob_count] = fopen('php://memory', 'a');
                    fwrite($blobs[$blob_count], $insert_values[$idx]);
                    rewind($blobs[$blob_count]);
                    $stmt->getClientStatement()
                        ->bindParam(':db_insert_placeholder_' . $max_placeholder++, $blobs[$blob_count], \PDO::PARAM_LOB);
                    // Pre-increment is faster in PHP than increment.
                    ++$blob_count;
                }
                else {
                    $stmt->getClientStatement()
                        ->bindParam(':db_insert_placeholder_' . $max_placeholder++, $insert_values[$idx]);
                }
            }
            // Check if values for a serial field has been passed.
            if (!empty($table_information->serial_fields)) {
                foreach ($table_information->serial_fields as $index => $serial_field) {
                    $serial_key = array_search($serial_field, $this->insertFields);
                    if ($serial_key !== FALSE) {
                        $serial_value = $insert_values[$serial_key];
                        // Sequences must be greater than or equal to 1.
                        if ($serial_value === NULL || !$serial_value) {
                            $serial_value = 1;
                        }
                        // Set the sequence to the bigger value of either the passed
                        // value or the max value of the column. It can happen that another
                        // thread calls nextval() which could lead to a serial number being
                        // used twice. However, trying to insert a value into a serial
                        // column should only be done in very rare cases and is not thread
                        // safe by definition.
                        $this->connection
                            ->query("SELECT setval('" . $table_information->sequences[$index] . "', GREATEST(MAX(" . $serial_field . "), :serial_value)) FROM {" . $this->table . "}", [
                            ':serial_value' => (int) $serial_value,
                        ]);
                    }
                }
            }
        }
        if (!empty($this->fromQuery)) {
            // bindParam stores only a reference to the variable that is followed when
            // the statement is executed. We pass $arguments[$key] instead of $value
            // because the second argument to bindParam is passed by reference and
            // the foreach statement assigns the element to the existing reference.
            $arguments = $this->fromQuery
                ->getArguments();
            foreach ($arguments as $key => $value) {
                $stmt->getClientStatement()
                    ->bindParam($key, $arguments[$key]);
            }
        }
        // Create a savepoint so we can rollback a failed query. This is so we can
        // mimic MySQL and SQLite transactions which don't fail if a single query
        // fails. This is important for tables that are created on demand. For
        // example, \Drupal\Core\Cache\DatabaseBackend.
        $this->connection
            ->addSavepoint();
        try {
            $stmt->execute(NULL, $this->queryOptions);
            if (isset($table_information->serial_fields[0])) {
                $last_insert_id = $stmt->fetchField();
            }
            $this->connection
                ->releaseSavepoint();
        } catch (\Exception $e) {
            $this->connection
                ->rollbackSavepoint();
            $this->connection
                ->exceptionHandler()
                ->handleExecutionException($e, $stmt, [], $this->queryOptions);
        }
        // Re-initialize the values array so that we can re-use this query.
        $this->insertValues = [];
        return $last_insert_id ?? NULL;
    }
    public function __toString() {
        // Create a sanitized comment string to prepend to the query.
        $comments = $this->connection
            ->makeComment($this->comments);
        // Default fields are always placed first for consistency.
        $insert_fields = array_merge($this->defaultFields, $this->insertFields);
        $insert_fields = array_map(function ($f) {
            return $this->connection
                ->escapeField($f);
        }, $insert_fields);
        // If we're selecting from a SelectQuery, finish building the query and
        // pass it back, as any remaining options are irrelevant.
        if (!empty($this->fromQuery)) {
            $insert_fields_string = $insert_fields ? ' (' . implode(', ', $insert_fields) . ') ' : ' ';
            $query = $comments . 'INSERT INTO {' . $this->table . '}' . $insert_fields_string . $this->fromQuery;
        }
        else {
            $query = $comments . 'INSERT INTO {' . $this->table . '} (' . implode(', ', $insert_fields) . ') VALUES ';
            $values = $this->getInsertPlaceholderFragment($this->insertValues, $this->defaultFields);
            $query .= implode(', ', $values);
        }
        try {
            // Fetch the list of blobs and sequences used on that table.
            $table_information = $this->connection
                ->schema()
                ->queryTableInformation($this->table);
            if (isset($table_information->serial_fields[0])) {
                // Use RETURNING syntax to get the last insert ID in the same INSERT
                // query, see https://www.postgresql.org/docs/12/dml-returning.html.
                $query .= ' RETURNING ' . $table_information->serial_fields[0];
            }
        } catch (DatabaseExceptionWrapper) {
            // If we fail to get the table information it is probably because the
            // table does not exist yet so adding the returning statement is pointless
            // because the query will fail. This happens for tables created on demand,
            // for example, cache tables.
        }
        return $query;
    }

}