I have table
CREATE TABLE nodes (
name VARCHAR(50) NOT NULL,
parent VARCHAR(50),
PRIMARY KEY (name),
FOREIGN KEY(parent) REFERENCES nodes (name) ON UPDATE cascade
);
I put some data
INSERT INTO nodes (name, parent) VALUES ('n1', NULL);
INSERT INTO nodes (name, parent) VALUES ('n11', 'n1');
INSERT INTO nodes (name, parent) VALUES ('n12', 'n1');
INSERT INTO nodes (name, parent) VALUES ('n13', 'n1');
Let's delete all
DELETE FROM nodes;
Nope, no way.
SQL Error [124] [S1000]: [SQLCODE: <-124>:<FOREIGN KEY constraint failed referential check upon DELETE of row in referenced table>]
[Location: <ServerLoop>]
[%msg: <At least 1 Row exists in table 'SQLUser.nodes' which references key 'NODESPKey2' - Foreign Key Constraint 'NODESFKey3', Field(s) 'parent' failed on referential action of NO ACTION>]
By update
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