Record ID written to state file as string

I have two tables selected from Oracle database. For one of these ID column value for last record is written back to state file as text

```
---
last_records:
app.application_log_vw:
id: '163431515.0'
```

Next run fails for this reason with

`OCIError: ORA-01722: invalid number`

Only difference between the two tables is in ID having little different datatype declaration. One having NUMBER(38) and the problematic one only NUMBER.

Ruby gem versions

```
ruby-oci8-2.2.11
activerecord-oracle_enhanced-adapter-6.1.6
activerecord-6.1.4.6
activesupport-6.1.4.6
activerecord-oracle_enhanced-adapter-6.1.6
fluent-plugin-sql-2.3.0
```

Reproduce the state-file write and next-run failure with Oracle columns declared as NUMBER(38) and NUMBER. Trace how the selected record ID is converted before it is written to the state file, then verify that the persisted value remains usable by the next query and no longer causes ORA-01722.

索引モデルが issue の本文から書いたものです。