> ## Documentation Index
> Fetch the complete documentation index at: https://www.pgschema.com/llms.txt
> Use this file to discover all available pages before exploring further.

# CREATE SEQUENCE

## Syntax

```sql theme={null}
create_sequence ::= CREATE SEQUENCE [ IF NOT EXISTS ] sequence_name
                    [ AS data_type ]
                    [ INCREMENT [ BY ] increment ]
                    [ MINVALUE minvalue | NO MINVALUE ] 
                    [ MAXVALUE maxvalue | NO MAXVALUE ]
                    [ START [ WITH ] start ]
                    [ CACHE cache ]
                    [ [ NO ] CYCLE ]
                    [ OWNED BY { table_name.column_name | NONE } ]

sequence_name ::= [schema.]name

data_type ::= smallint | integer | bigint

increment ::= integer

minvalue ::= integer

maxvalue ::= integer  

start ::= integer

cache ::= integer
```

pgschema understands the following `CREATE SEQUENCE` features:

* **Schema-qualified names**: Sequences can be defined in specific schemas
* **Data types**: bigint (default), integer, smallint
* **START WITH**: Initial value of the sequence (default: 1)
* **INCREMENT BY**: Step value for sequence increments (default: 1)
* **MINVALUE/NO MINVALUE**: Minimum value for the sequence (default: 1 for ascending sequences)
* **MAXVALUE/NO MAXVALUE**: Maximum value for the sequence (default: 2^63-1 for bigint)
* **CYCLE/NO CYCLE**: Whether the sequence should wrap around when reaching min/max values
* **OWNED BY**: Associates the sequence with a table column for automatic cleanup

## Canonical Format

When generating migration SQL, pgschema produces sequences in the following canonical format:

```sql theme={null}
CREATE SEQUENCE IF NOT EXISTS [schema.]sequence_name
[ START WITH start_value ]
[ INCREMENT BY increment_value ]
[ MINVALUE min_value ]
[ MAXVALUE max_value ]
[ CYCLE ];
```

**Key characteristics of the canonical format:**

* Always uses `IF NOT EXISTS` for CREATE operations
* Only includes parameters that differ from PostgreSQL defaults:
  * START WITH is included if not 1
  * INCREMENT BY is included if not 1
  * MINVALUE is included if not 1
  * MAXVALUE is included if not the data type maximum (9223372036854775807 for bigint)
  * CYCLE is only included if enabled (default is NO CYCLE)
* For ALTER operations: `ALTER SEQUENCE sequence_name parameter_changes;`
* For DROP operations: `DROP SEQUENCE IF EXISTS sequence_name CASCADE;`
* CACHE specifications are included when they differ from the default (1)
* Data type specifications (AS bigint/integer/smallint) are included when explicitly specified
* OWNED BY relationships are tracked but managed separately through column dependencies