/**
* Drops the index with the specified name from this database.
*
* @param indexname the name of the index to drop
* @param ifExists if true and if the Index to drop does not exist, fail silently, else throw
* @param session the execution context
* @throws HsqlException if the index does not exist, the session lacks the permission or the
* operation violates database integrity
*/
void dropIndex(Session session, String indexname, String tableName, boolean ifExists)
throws HsqlException {
Table t = findUserTableForIndex(session, indexname);
if (t == null) {
if (ifExists) {
return;
} else {
throw Trace.error(Trace.INDEX_NOT_FOUND, indexname);
}
}
if (tableName != null && !t.getName().name.equals(tableName)) {
throw Trace.error(Trace.INDEX_NOT_FOUND, indexname);
}
t.checkDropIndex(indexname, null);
// fredt@users 20020405 - patch 1.7.0 by fredt - drop index bug
// see Table.moveDefinition();
session.commit();
session.setScripting(!t.isTemp());
TableWorks tw = new TableWorks(session, t);
tw.dropIndex(indexname);
}
/** Drops a trigger with the specified name in the given context. */
void dropTrigger(Session session, String name) throws HsqlException {
boolean found = triggerNameList.containsName(name);
Trace.check(found, Trace.TRIGGER_NOT_FOUND, name);
HsqlName tableName = (HsqlName) triggerNameList.removeName(name);
Table t = this.findUserTable(session, tableName.name);
t.dropTrigger(name);
session.setScripting(!t.isTemp());
}
/**
* Drops the specified user-defined view or table from this Database object.
*
* <p>The process of dropping a table or view includes:
*
* <OL>
* <LI>checking that the specified Session's currently connected User has the right to perform
* this operation and refusing to proceed if not by throwing.
* <LI>checking for referential constraints that conflict with this operation and refusing to
* proceed if they exist by throwing.
* <LI>removing the specified Table from this Database object.
* <LI>removing any exported foreign keys Constraint objects held by any tables referenced by
* the table to be dropped. This is especially important so that the dropped Table ceases to
* be referenced, eventually allowing its full garbage collection.
* <LI>
* </OL>
*
* <p>
*
* @param name of the table or view to drop
* @param ifExists if true and if the Table to drop does not exist, fail silently, else throw
* @param isView true if the name argument refers to a View
* @param session the connected context in which to perform this operation
* @throws HsqlException if any of the checks listed above fail
*/
void dropTable(Session session, String name, boolean ifExists, boolean isView)
throws HsqlException {
Table toDrop = null;
int dropIndex = -1;
for (int i = 0; i < tTable.size(); i++) {
toDrop = (Table) tTable.get(i);
if (toDrop.equals(session, name) && isView == toDrop.isView()) {
dropIndex = i;
break;
} else {
toDrop = null;
}
}
if (dropIndex == -1) {
if (ifExists) {
return;
} else {
throw Trace.error(isView ? Trace.VIEW_NOT_FOUND : Trace.TABLE_NOT_FOUND, name);
}
}
if (!toDrop.isTemp()) {
session.checkDDLWrite();
}
if (isView) {
checkViewIsInView((View) toDrop);
} else {
checkTableIsReferenced(toDrop);
checkTableIsInView(toDrop.tableName.name);
}
tTable.remove(dropIndex);
removeExportedKeys(toDrop);
userManager.removeDbObject(toDrop.getName());
triggerNameList.removeOwner(toDrop.tableName);
indexNameList.removeOwner(toDrop.tableName);
constraintNameList.removeOwner(toDrop.tableName);
toDrop.dropTriggers();
toDrop.drop();
session.setScripting(!toDrop.isTemp());
session.commit();
}
/**
* Drops the index with the specified name from this database.
*
* @param indexname the name of the index to drop
* @param session the execution context
* @throws SQLException if the index does not exist, the session lacks the permission or the
* operation violates database integrity
*/
void dropIndex(String indexname, Session session) throws SQLException {
Table t = findUserTableForIndex(indexname, session);
if (t == null) {
throw Trace.error(Trace.INDEX_NOT_FOUND, indexname);
}
t.checkDropIndex(indexname, null);
// fredt@users 20020405 - patch 1.7.0 by fredt - drop index bug
// see Table.moveDefinition();
session.commit();
session.setScripting(!t.isTemp());
TableWorks tw = new TableWorks(t);
tw.dropIndex(indexname);
}
/**
* Drops a trigger with the specified name from this Database
*
* @param name of the trigger to drop
* @param session execution context
* @throws SQLException if a database access error occurs
*/
void dropTrigger(String name, Session session) throws SQLException {
boolean found = false;
// look in each trigger list of each type of trigger for each table
for (int i = 0, tsize = tTable.size(); i < tsize; i++) {
Table t = (Table) tTable.get(i);
int numTrigs = TriggerDef.numTrigs();
for (int tv = 0; tv < numTrigs; tv++) {
HsqlArrayList v = t.vTrigs[tv];
for (int tr = v.size() - 1; tr >= 0; tr--) {
TriggerDef td = (TriggerDef) v.get(tr);
if (td.name.equals(name)) {
// fredt@users 20020221 - patch 513005 by sqlbob@users (RMP)
session.setScripting(!td.table.isTemp());
v.remove(tr);
found = true;
if (Trace.TRACE) {
Trace.trace("Trigger dropped " + name);
}
}
}
}
}
Trace.check(found, Trace.TRIGGER_NOT_FOUND, name);
// boucherb@users 20021128 - enforce unique trigger names
triggerNameList.removeName(name);
// ---
}
/**
* Drops the specified user-defined view or table from this Database object.
*
* <p>The process of dropping a table or view includes:
*
* <OL>
* <LI>checking that the specified Session's currently connected User has the right to perform
* this operation and refusing to proceed if not by throwing.
* <LI>checking for referential constraints that conflict with this operation and refusing to
* proceed if they exist by throwing.
* <LI>removing the specified Table from this Database object.
* <LI>removing any exported foreign keys Constraint objects held by any tables referenced by
* the table to be dropped. This is especially important so that the dropped Table ceases to
* be referenced, eventually allowing its full garbage collection.
* <LI>
* </OL>
*
* <p>
*
* @param name of the table or view to drop
* @param ifExists if true and if the Table to drop does not exist, fail silently, else throw
* @param isView true if the name argument refers to a View
* @param session the connected context in which to perform this operation
* @throws SQLException if any of the checks listed above fail
*/
void dropTable(String name, boolean ifExists, boolean isView, Session session)
throws SQLException {
Table toDrop = null;
int dropIndex = -1;
int refererIndex = -1;
Enumeration constraints = null;
Constraint currentConstraint = null;
Table refTable = null;
boolean isRef = false;
boolean isSelfRef = false;
for (int i = 0; i < tTable.size(); i++) {
toDrop = (Table) tTable.get(i);
if (toDrop.equals(name, session) && isView == toDrop.isView()) {
dropIndex = i;
break;
} else {
toDrop = null;
}
}
if (dropIndex == -1) {
if (ifExists) {
return;
} else {
throw Trace.error(isView ? Trace.VIEW_NOT_FOUND : Trace.TABLE_NOT_FOUND, name);
}
}
constraints = toDrop.getConstraints().elements();
while (constraints.hasMoreElements()) {
currentConstraint = (Constraint) constraints.nextElement();
if (currentConstraint.getType() != Constraint.MAIN) {
continue;
}
refTable = currentConstraint.getRef();
isRef = (refTable != null);
isSelfRef = (isRef && toDrop.equals(refTable));
if (isRef && !isSelfRef) {
// cover the case where the referencing table
// may have already been dropped
for (int k = 0; k < tTable.size(); k++) {
if (refTable.equals(tTable.get(k))) {
refererIndex = k;
break;
}
}
if (refererIndex != -1) {
// tony_lai@users 20020820 - patch 595156
throw Trace.error(
Trace.INTEGRITY_CONSTRAINT_VIOLATION,
currentConstraint.getName().name + " table: " + refTable.getName().name);
}
}
}
tTable.remove(dropIndex);
removeExportedKeys(toDrop);
aAccess.removeDbObject(toDrop.getName());
triggerNameList.removeOwner(toDrop.tableName);
indexNameList.removeOwner(toDrop.tableName);
toDrop.drop();
session.setScripting(!toDrop.isTemp());
session.commit();
}
