ALTER FIELD

The ALTER statement can be used to change authentication access and behaviour, global parameters, table configurations, table events, schema definitions, and indexes.

The ALTER FIELD statement is used to change or entirely drop clauses of a defined field on a table.

Statement syntax

SurrealQL Syntax

ALTER FIELD [ IF EXISTS ] ON [ TABLE ] @table 
[ 
    DROP TYPE |
    DROP FLEXIBLE |
    DROP READONLY |
    DROP VALUE |
    DROP ASSERT |
    DROP DEFAULT |
    DROP COMMENT |
    DROP REFERENCE |
    FLEXIBLE |
    READONLY |
    REFERENCE |
    TYPE @type |
    VALUE @value |
    ASSERT @expression |
    DEFAULT [ ALWAYS ] @expression |
    [ PERMISSIONS [ NONE | FULL
		| FOR select @expression
		| FOR create @expression
		| FOR update @expression
		| FOR delete @expression
	] ]
    COMMENT @string |
]

Examples

As ALTER FIELD contains the same clauses available in a DEFINE FIELD statement, be sure to see that page for more examples.

Here is one example in which the name field is defined for a record user:

DEFINE FIELD name ON user TYPE string;

Later on, a database-wide parameter is defined to disallow certain user names. This can be followed up with an ALTER FIELD statement to add the ASSERT clause to it.

DEFINE PARAM $DISALLOWED_NAMES VALUE ["Lord British", "Lord Blackthorn"];
ALTER FIELD name ON user ASSERT $value NOT IN $DISALLOWED_NAMES;
CREATE user SET name = "Lord British";

Output

"Found 'Lord British' for field `name`, with record `user:yn4yttkg5w683q2937bq`, but field must conform to: $value NOTINSIDE $DISALLOWED_NAMES""

Statement syntax

Examples

See also