Oracle AI Database 26ai New Features: A Practical DBA Guide

Oracle AI Database 26ai is not just another version number to memorize for certification or patch planning. It feels like Oracle is telling DBAs and developers: AI is no longer something sitting outside the database. It is becoming part of the database conversation itself.

But if you are a working DBA, you probably do not have time for marketing noise. You want to know what changed, what is useful, what can break, and what deserves lab time before anyone talks about production. That is how this series is written: simple language, practical checks, and SQL*Plus-style examples you can actually relate to.

This series will continue chapter by chapter:

1. Oracle 26ai new features overview
2. Oracle 26ai architecture
3. Tablespace and space management
4. User and privilege management
5. Network configuration
6. Backup and recovery
7. Patching
8. Upgrade planning
9. Performance tuning
10. Security and auditing
11. Data Guard and high availability
12. Daily DBA checks

Why Oracle 26ai matters

The name says AI, but DBAs should not file this release under "developer-only features." There are plenty of changes here that touch normal administration: SQL syntax, security, access control, SQL*Plus usability, application connectivity, availability, and performance.

For a DBA, the biggest question is not "What is new?" The real question is:

Which new features can reduce operational risk, simplify administration, or help developers build faster without creating a messy database estate?

That is the lens we will use.

1. AI Vector Search

AI Vector Search lets Oracle store and search vector embeddings. A vector is a numeric representation of meaning. Instead of searching only by exact words, the database can search by semantic similarity.

Simple example:

• Keyword search asks: "Does this row contain the word patching?"
• Vector search asks: "Which rows are closest in meaning to this question about patching?"

That matters for knowledge bases, support systems, document search, recommendation engines, fraud analysis, and AI assistants that need trusted enterprise data.

A simplified table design might look like this:

CREATE TABLE dba_knowledge_base (
    doc_id      NUMBER GENERATED BY DEFAULT AS IDENTITY,
    title       VARCHAR2(200),
    category    VARCHAR2(50),
    doc_text    CLOB,
    embedding   VECTOR,
    created_at  TIMESTAMP DEFAULT SYSTIMESTAMP,
    CONSTRAINT dba_kb_pk PRIMARY KEY (doc_id)
);

A simplified semantic search pattern looks like this:

SELECT doc_id,
       title,
       category
FROM   dba_knowledge_base
ORDER  BY VECTOR_DISTANCE(embedding, :question_vector)
FETCH  FIRST 5 ROWS ONLY;

SQL*Plus style example

SQL> SELECT title, category
  2  FROM   dba_knowledge_base
  3  ORDER  BY VECTOR_DISTANCE(embedding, :question_vector)
  4  FETCH  FIRST 3 ROWS ONLY;

TITLE                                      CATEGORY
----------------------------------------   ----------------
How to apply an Oracle Release Update      patching
How to troubleshoot datapatch failures     patching
How to validate invalid objects            daily_dba

DBA takeaway: AI Vector Search makes the database more useful for AI applications, but DBAs must still manage normal fundamentals: memory, indexes, privileges, backup, performance, and data lifecycle.

2. JSON Relational Duality

Many applications want JSON documents. DBAs still want relational tables, constraints, indexing, backup, and SQL visibility. JSON Relational Duality helps both sides.

The idea is simple: the same data can be viewed and updated as JSON documents or relational rows.

Why this matters:

• Developers work with JSON naturally.
• DBAs keep relational structure and data integrity.
• Applications can avoid unnecessary object-relational mapping complexity.
• Data is not trapped in a separate document-only model.

Example concept:

-- Relational tables remain the system of record
CUSTOMERS
ORDERS
ORDER_ITEMS

-- A JSON duality view can expose the order as one document
{
  "orderId": 1001,
  "customer": "Asha Rao",
  "items": [
    { "sku": "DBA-BOOK", "qty": 1 },
    { "sku": "LAB-SCRIPT", "qty": 2 }
  ]
}

DBA takeaway: this feature is useful when developers want document-style access but the organization still needs relational governance.

3. SQL Firewall

Security is one of the most DBA-relevant areas in Oracle 26ai. SQL Firewall is included in Oracle AI Database and is designed to help detect and block unauthorized SQL activity.

In plain language, SQL Firewall learns or defines what SQL patterns are expected, then helps block SQL that does not match the allowed behavior.

This can help with:

• SQL injection risk
• unexpected application behavior
• compromised accounts
• unusual SQL execution paths

A DBA mindset for SQL Firewall:

1. Understand the application SQL workload.
2. Capture or define allowed SQL patterns.
3. Monitor violations before blocking aggressively.
4. Move to enforcement after testing.
5. Review after application releases.

SQL Firewall should not replace secure coding, least privilege, or patching. Think of it as another layer.

4. Schema Privileges

Traditional privilege management can become messy. DBAs often grant object privileges one by one, or they grant too much because it is faster.

Oracle 26ai highlights schema-level privileges to simplify access control. This allows DBAs to grant privileges at the schema level instead of managing every object individually.

A simplified pattern:

-- Conceptual example: grant access at schema level
GRANT SELECT ANY TABLE ON SCHEMA reporting TO app_read_role;

Why DBAs should care:

• Cleaner privilege administration
• Less object-by-object grant maintenance
• Better separation between schemas and application roles
• Easier onboarding for developers and reporting users

DBA takeaway: schema-level privileges can reduce operational work, but they still need naming standards and periodic access reviews.

5. DB_DEVELOPER_ROLE

Oracle 26ai also highlights a developer role. The purpose is to give application developers a practical set of privileges for building applications without handing them broad DBA rights.

This is helpful because many environments have a common problem:

• Developers need enough access to build.
• DBAs do not want to grant powerful system privileges casually.
• Security teams want cleaner access boundaries.

A typical workflow might be:

CREATE USER app_dev IDENTIFIED BY "Use-A-Strong-Password";
GRANT CREATE SESSION TO app_dev;
GRANT DB_DEVELOPER_ROLE TO app_dev;

DBA takeaway: this can make development environments easier to manage, but production access should still be tightly controlled.

6. SQL BOOLEAN data type

Oracle has supported PL/SQL Boolean logic for a long time, but SQL BOOLEAN support is a major usability improvement for developers.

Instead of storing flags as CHAR(1), NUMBER(1), or VARCHAR2 values like Y/N, applications can use a more natural Boolean style.

Example:

CREATE TABLE feature_flags (
    feature_name VARCHAR2(100) PRIMARY KEY,
    enabled      BOOLEAN
);

INSERT INTO feature_flags VALUES ('new_checkout', TRUE);
INSERT INTO feature_flags VALUES ('legacy_report', FALSE);

SELECT feature_name, enabled
FROM   feature_flags;

SQL*Plus style output:

SQL> SELECT feature_name, enabled
  2  FROM   feature_flags;

FEATURE_NAME                         ENABLED
-----------------------------------  -------
new_checkout                         TRUE
legacy_report                        FALSE

DBA takeaway: BOOLEAN can clean up application schemas, but migration from old Y/N or 0/1 columns should be planned carefully.

7. SELECT without FROM

Developers coming from PostgreSQL, MySQL, or SQL Server often expect simple expressions without selecting from DUAL. Oracle 26ai includes support for SELECT without FROM.

Old style:

SELECT SYSDATE FROM dual;

New style:

SELECT SYSDATE;

SQL*Plus style output:

SQL> SELECT SYSDATE;

SYSDATE
---------
03-JUL-26

DBA takeaway: this is small but developer-friendly. It reduces friction for teams working across multiple database platforms.

8. Direct joins for UPDATE and DELETE

Oracle 26ai includes SQL syntax improvements that make some update and delete operations easier to write.

A practical use case is updating rows in one table based on matching rows in another table.

Conceptual example:

UPDATE customers c
SET    c.status = 'INACTIVE'
FROM   customer_activity a
WHERE  c.customer_id = a.customer_id
AND    a.last_login_date < ADD_MONTHS(SYSDATE, -24);

DBA takeaway: SQL syntax improvements help developers write clearer SQL, but DBAs should still check execution plans before large updates or deletes.

9. Priority Transactions

Priority Transactions help when a low-priority transaction blocks a high-priority transaction. Oracle can automatically abort lower-priority blockers to protect important work.

Where this matters:

• OLTP systems
• payment flows
• order processing
• operational dashboards
• critical batch windows

DBA takeaway: this is not a substitute for good application design, but it gives DBAs another tool for reducing the impact of blocking sessions.

A simple blocking investigation still matters:

SELECT blocking_session,
       sid,
       serial#,
       wait_class,
       event,
       seconds_in_wait
FROM   v$session
WHERE  blocking_session IS NOT NULL;

SQL*Plus style output:

BLOCKING_SESSION   SID   SERIAL#   WAIT_CLASS    EVENT                  SECONDS_IN_WAIT
----------------   ---   -------   ----------    --------------------   ---------------
125                188   44721     Application   enq: TX - row lock     92

10. SQL*Plus improvements

Oracle 26ai includes SQL*Plus improvements such as commands around connection visibility, pinging, error details, and configuration.

For DBAs, this matters because SQL*Plus is still everywhere:

• patching checks
• upgrade scripts
• RMAN-adjacent validation
• emergency troubleshooting
• automation wrappers
• simple connectivity testing

Useful DBA-style checks include:

SQL> SHOW USER
USER is "SYS"

SQL> SHOW CON_NAME
CON_NAME
------------------------------
FREEPDB1

SQL> SHOW CONNECTION
-- Displays current connection details in supported 26ai SQL*Plus clients

DBA takeaway: small client improvements can save time during incidents, especially when many terminals are open and you need to confirm where you are connected.

11. TLS 1.3 and security enhancements

Oracle 26ai includes important security improvements, including TLS 1.3 support, SQL Firewall, authentication improvements, and encryption-related updates.

DBAs should treat this as a planning area, not just a feature list.

Checklist:

• Review sqlnet.ora and listener.ora standards.
• Confirm supported client versions.
• Review wallet usage.
• Validate application connection strings.
• Test TLS changes in lower environments.
• Document rollback steps.

Example network check:

$ tnsping salesdb

TNS Ping Utility for Linux: Version 26.0.0.0.0
Used parameter files:
/u01/app/oracle/product/26ai/network/admin/sqlnet.ora

OK (30 msec)

12. What DBAs should do first

If you are preparing for Oracle 26ai, do not start by enabling every new feature. Start with understanding and readiness.

Practical DBA checklist

1. Build a lab database.
2. Confirm client compatibility.
3. Review new SQL syntax with developers.
4. Test SQL*Plus client behavior.
5. Review security features like SQL Firewall and TLS 1.3.
6. Identify schemas that could benefit from schema privileges.
7. Test AI Vector Search only with a clear use case.
8. Document operational steps before production.
9. Train developers on what is allowed in production.
10. Add monitoring before enabling new workloads.

Simple lab queries for the next post

Use these checks when you begin exploring an Oracle 26ai environment:

SELECT banner_full
FROM   v$version;

SHOW CON_NAME

SELECT name, open_mode
FROM   v$pdbs
ORDER  BY name;

SELECT username, account_status, common
FROM   dba_users
ORDER  BY username;

SELECT tablespace_name, status, contents
FROM   dba_tablespaces
ORDER  BY tablespace_name;

SQL*Plus style output:

SQL> SELECT banner_full FROM v$version;

BANNER_FULL
--------------------------------------------------------------------------------
Oracle AI Database 26ai Enterprise Edition Release 26.0.0.0.0 - Production

SQL> SHOW CON_NAME

CON_NAME
------------------------------
FREEPDB1

Final thought

My practical view: do not learn Oracle 26ai as a giant feature list. Learn it as a DBA map. Some features help developers. Some help security. Some help operations. Some will not matter to your environment at all, and that is fine.

The right way to learn it is chapter by chapter. Start with the feature map, then go deeper into architecture, storage, users, networking, patching, upgrades, and performance.

In the next article, we will cover Oracle 26ai architecture in a DBA-friendly way: instance, database, CDB, PDB, memory, background processes, listener, services, and where SQL*Plus fits into daily administration.

References

• Oracle AI Database 26ai New Features Guide
• Oracle 26ai Feature Highlights
• Oracle 26ai Application Development General Features