Icon (+) to add a column to the list repeat the steps above and click the
To specify a column in the foreign table. To specify the name of the table in which the comparison column(s) resides. To specify the column in the current table that will be compared to the foreign table. A Foreign Key constraint requires that one or more columns of a table must only contain values that match values in the referenced column(s) of a row of a referenced table: Tab to specify one or more reference column(s). Position to disable the automatic index feature. Position to instruct the server to validate the existing table content (against a foreign key or check constraint) when you save modifications to this dialog. To specify that a single foreign key column may be null if any column is null, the row is not required to have a match in the referenced table. To indicate that all columns of a multicolumn foreign key must be null if any column is null if all columns are null, the row is not required to have a match in the referenced table. Switch specify the type of matching that is enforced by the constraint: Position to specify the timing of the constraint is deferred to the end of the statement. Position to specify the timing of the constraint is deferrable and can be postponed until the end of the statement. Tab to define the foreign key constraint: Store notes about the foreign key constraint in the Tab to identify the foreign key constraint:įield to add a descriptive name for the foreign key.
#Postgresql pgadmin 4 foreign key allows to delete data code#
Tab displays the SQL code generated by dialog selections. A foreign key constraint cannot be defined between a temporary table and a permanent table.ĭialog organizes the development of a foreign key constraint through the following dialog tabs:
A foreign key constraint maintains referential integrity between two tables. Dialog to specify the behavior of a foreign key constraint.
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