package liquibase.change.core;
import liquibase.change.*;
import liquibase.database.Database;
import liquibase.database.core.SQLiteDatabase;
import liquibase.snapshot.SnapshotGeneratorFactory;
import liquibase.statement.SqlStatement;
import liquibase.statement.core.DropForeignKeyConstraintStatement;
import liquibase.structure.core.ForeignKey;
/**
* Drops an existing foreign key constraint.
*/
@DatabaseChange(name="dropForeignKeyConstraint", description = "Drops an existing foreign key", priority = ChangeMetaData.PRIORITY_DEFAULT, appliesTo = "foreignKey")
public class DropForeignKeyConstraintChange extends AbstractChange {
private String baseTableCatalogName;
private String baseTableSchemaName;
private String baseTableName;
private String constraintName;
@DatabaseChangeProperty(mustEqualExisting ="foreignKey.table.catalog", since = "3.0")
public String getBaseTableCatalogName() {
return baseTableCatalogName;
}
public void setBaseTableCatalogName(String baseTableCatalogName) {
this.baseTableCatalogName = baseTableCatalogName;
}
@DatabaseChangeProperty(mustEqualExisting ="foreignKey.table.schema")
public String getBaseTableSchemaName() {
return baseTableSchemaName;
}
public void setBaseTableSchemaName(String baseTableSchemaName) {
this.baseTableSchemaName = baseTableSchemaName;
}
@DatabaseChangeProperty(mustEqualExisting = "foreignKey.table", description = "Name of the table containing the column constrained by the foreign key")
public String getBaseTableName() {
return baseTableName;
}
public void setBaseTableName(String baseTableName) {
this.baseTableName = baseTableName;
}
@DatabaseChangeProperty(mustEqualExisting = "foreignKey", description = "Name of the foreign key constraint to drop", exampleValue = "fk_address_person")
public String getConstraintName() {
return constraintName;
}
public void setConstraintName(String constraintName) {
this.constraintName = constraintName;
}
@Override
public SqlStatement[] generateStatements(Database database) {
if (database instanceof SQLiteDatabase) {
// return special statements for SQLite databases
return generateStatementsForSQLiteDatabase();
}
return new SqlStatement[]{
new DropForeignKeyConstraintStatement(
getBaseTableCatalogName(),
getBaseTableSchemaName(),
getBaseTableName(),
getConstraintName()),
};
}
@Override
public ChangeStatus checkStatus(Database database) {
try {
return new ChangeStatus().assertComplete(!SnapshotGeneratorFactory.getInstance().has(new ForeignKey(getConstraintName(), getBaseTableCatalogName(), getBaseTableSchemaName(), getBaseTableCatalogName()), database), "Foreign key exists");
} catch (Exception e) {
return new ChangeStatus().unknown(e);
}
}
private SqlStatement[] generateStatementsForSQLiteDatabase() {
// SQLite does not support foreign keys until now.
// See for more information: http://www.sqlite.org/omitted.html
// Therefore this is an empty operation...
return new SqlStatement[]{};
}
@Override
public String getConfirmationMessage() {
return "Foreign key " + getConstraintName() + " dropped";
}
@Override
public String getSerializedObjectNamespace() {
return STANDARD_CHANGELOG_NAMESPACE;
}
}