Package jakarta.persistence

Annotation Interface Column

@Target({METHOD,FIELD}) @Retention(RUNTIME) public @interface Column
Specifies the column mapped by the annotated persistent property or field.

If no Column annotation is explicitly specified, the default values apply.

Example 1: 

@Column(name = "DESC", nullable = false, length = 512)
public String getDescription() { return description; }

Example 2: 

@Column(name = "DESC",
        columnDefinition = "CLOB NOT NULL",
        table = "EMP_DETAIL")
@Lob
public String getDescription() { return description; }

Example 3: 

@Column(name = "ORDER_COST", updatable = false, precision = 12, scale = 2)
public BigDecimal getCost() { return cost; }
Since:
1.0

  • Optional Element Summary Link icon

    Optional Elements
    Modifier and Type
    Optional Element
    Description
    CheckConstraint[]
    check
    (Optional) Check constraints to be applied to the column.
    String
    columnDefinition
    (Optional) The SQL fragment that is used when generating the DDL for the column.
    String
    comment
    (Optional) A comment to be applied to the column.
    boolean
    insertable
    (Optional) Whether the column is included in SQL INSERT statements generated by the persistence provider.
    int
    length
    (Optional) The column length.
    String
    name
    (Optional) The name of the column.
    boolean
    nullable
    (Optional) Whether the database column is nullable.
    String
    options
    (Optional) A SQL fragment appended to the generated DDL which declares this column.
    int
    precision
    (Optional) The precision for a decimal (exact numeric) column.
    int
    scale
    (Optional) The scale for a decimal (exact numeric) column.
    String
    table
    (Optional) The name of the table that contains the column.
    boolean
    unique
    (Optional) Whether the column is a unique key.
    boolean
    updatable
    (Optional) Whether the column is included in SQL UPDATE statements generated by the persistence provider.

  • Element Details

    • name Link icon

      String name
      (Optional) The name of the column. Defaults to the property or field name.
      Default:
      ""

    • unique Link icon

      boolean unique
      (Optional) Whether the column is a unique key. This is a shortcut for the UniqueConstraint annotation at the table level and is useful for when the unique key constraint corresponds to only a single column. This constraint applies in addition to any constraint entailed by the primary key mapping and to constraints specified at the table level.
      Default:
      false

    • nullable Link icon

      boolean nullable
      (Optional) Whether the database column is nullable.
      Default:
      true

    • insertable Link icon

      boolean insertable
      (Optional) Whether the column is included in SQL INSERT statements generated by the persistence provider.
      Default:
      true

    • updatable Link icon

      boolean updatable
      (Optional) Whether the column is included in SQL UPDATE statements generated by the persistence provider.
      Default:
      true

    • columnDefinition Link icon

      String columnDefinition
      (Optional) The SQL fragment that is used when generating the DDL for the column.

      Defaults to the generated SQL to create a column of the inferred type.

      Default:
      ""

    • options Link icon

      String options
      (Optional) A SQL fragment appended to the generated DDL which declares this column. May not be used in conjunction with columnDefinition().
      Since:
      3.2
      Default:
      ""

    • table Link icon

      String table
      (Optional) The name of the table that contains the column. If absent the column is assumed to be in the primary table.
      Default:
      ""

    • length Link icon

      int length
      (Optional) The column length. (Applies only if a string-valued column is used.)
      Default:
      255

    • precision Link icon

      int precision
      (Optional) The precision for a decimal (exact numeric) column. (Applies only if a decimal column is used.) Value must be set by developer if used when generating the DDL for the column.
      Default:
      0

    • scale Link icon

      int scale
      (Optional) The scale for a decimal (exact numeric) column. (Applies only if a decimal column is used.)
      Default:
      0

    • check Link icon

      CheckConstraint[] check
      (Optional) Check constraints to be applied to the column. These are only used if table generation is in effect.
      Since:
      3.2
      Default:
      {}

    • comment Link icon

      String comment
      (Optional) A comment to be applied to the column. This is only used if table generation is in effect.
      Since:
      3.2
      Default:
      ""