共用方式為

Rules for Updating Tab, RI Builder

  • 發行項

The Rules for Updating tab in the Referential Integrity Builder specifies rules to apply when the key value in the parent table is modified. This builder also has the Rules for Deleting tab and the Rules for Inserting tab.

  • Cascade
    Specifies that changes in the fields of the Primary or Candidate key of the parent table are reflected in related child tables. If you select this option, any time you change any of those fields in the parent table, Microsoft Visual FoxPro automatically changes the corresponding values in all related child table records.

  • Restrict
    Prevents modification of values in fields of the Primary or Candidate key of the parent table so there are no orphaned records in the child table.

  • Ignore
    Allows you to update records in the parent table, even if there are related records in the child table.

  • Referential Integrity Grid
    Parent Table displays the name of the table in the database relation containing the primary or candidate index.

    Child Table displays the name of the child table in the database relation.

    Update displays the update rules for referential integrity for the relation. Possible values are Cascade, Restrict, or Ignore. You can change the settings by selecting the field, which will present a drop-down list of the choices.

    Delete displays the delete rules for the referential integrity for the relation. Possible values are Cascade, Restrict, or Ignore. You can change the settings by selecting the field, which will present a drop-down list of the choices.

    Insert displays the insert rules for the referential integrity for the relation. Possible values are Cascade, Restrict, or Ignore. You can change the settings by selecting the field, which will present a drop-down list of the choices.

    Parent Tag grid column displays the tag name of the index in the Primary or Candidate in the Parent table.

    Child Tag grid column displays the tag name of the index in the child table.

See Also

Referential Integrity Builder | Rules for Deleting Tab | Rules for Inserting Tab