Can my DB?

CREATE SEQUENCE order_seq
  START WITH 1000
  INCREMENT BY 1
  NO CYCLE;

-- Advance and return next value
SELECT NEXTVAL('order_seq');

-- Return current value (within session)
SELECT CURRVAL('order_seq');

-- Reset sequence to a specific value
SELECT SETVAL('order_seq', 5000);

• SERIAL / BIGSERIAL auto-create a sequence behind the column. For new code, prefer GENERATED AS IDENTITY (10+).
• CACHE n preallocates n values per session to reduce cross-session contention, at the cost of larger gaps if a session exits.

• Not supported. Auto-increment lives on the column via AUTO_INCREMENT.
• A single-row counter table plus SELECT LAST_INSERT_ID(new_val) is the common substitute for a standalone counter.

CREATE SEQUENCE order_seq
  START WITH 1000
  INCREMENT BY 1
  CACHE 50;

-- Advance and return next value
SELECT NEXTVAL(order_seq);

-- Return last used value in session
SELECT LASTVAL(order_seq);

-- Reset sequence
SELECT SETVAL(order_seq, 5000);

• Added in 10.3. Syntax is broadly compatible with Oracle and PostgreSQL.
• Can be used as a column default: col INT DEFAULT NEXTVAL(seq).

CREATE SEQUENCE order_seq
  START WITH 1000
  INCREMENT BY 1
  CACHE 20
  NOCYCLE;

-- Get next value
SELECT order_seq.NEXTVAL FROM DUAL;

-- Get current value (within session)
SELECT order_seq.CURRVAL FROM DUAL;

• CACHE preallocates values in SGA memory to cut contention on hot sequences; rollbacks and instance failures can leave gaps.
• 12c+ allows sequence.NEXTVAL directly as a column DEFAULT — no more FROM DUAL workaround.

CREATE SEQUENCE dbo.order_seq
  AS INT
  START WITH 1000
  INCREMENT BY 1
  CACHE 50
  NO CYCLE;

-- Get next value
SELECT NEXT VALUE FOR dbo.order_seq;

-- Batch allocation
EXEC sp_sequence_get_range
  @sequence_name = N'dbo.order_seq',
  @range_size = 100,
  @range_first_value = @first_value OUTPUT;

• Added in 2012. NEXT VALUE FOR can appear in DEFAULT, INSERT, and SELECT; no CURRVAL.
• sp_sequence_get_range reserves a batch of values in one call.

• Not supported. INTEGER PRIMARY KEY aliases the rowid and auto-increments; AUTOINCREMENT additionally prevents rowid reuse.

• No sequence object despite the PostgreSQL lineage. Use IDENTITY or GENERATED BY DEFAULT AS IDENTITY instead.

CREATE SEQUENCE order_seq
  AS INTEGER
  START WITH 1000
  INCREMENT BY 1
  CACHE 20
  NO CYCLE;

-- Get next value
VALUES NEXTVAL FOR order_seq;

-- Get previous value (within session)
VALUES PREVVAL FOR order_seq;

• NEXTVAL FOR / PREVVAL FOR is the DB2 spelling for NEXTVAL / CURRVAL. Usable in DEFAULT and INSERT.

CREATE SEQUENCE order_seq
  START = 1000
  INCREMENT = 1;

-- Use in a query
SELECT order_seq.NEXTVAL;

• Parameters are START = n and INCREMENT = n, not START WITH / INCREMENT BY. NEXTVAL only; no CURRVAL.
• Values aren't contiguous under concurrency — expect gaps.

• Not supported. GENERATE_UUID() covers unique string ids; otherwise, generate ids upstream.