use of org.apache.derby.iapi.sql.dictionary.ConstraintDescriptorList in project derby by apache.
the class RenameConstantAction method execGutsRenameColumn.
// do necessary work for rename column at execute time.
private void execGutsRenameColumn(TableDescriptor td, Activation activation) throws StandardException {
ColumnDescriptor columnDescriptor = null;
int columnPosition = 0;
ConstraintDescriptorList constraintDescriptorList;
ConstraintDescriptor constraintDescriptor;
LanguageConnectionContext lcc = activation.getLanguageConnectionContext();
DataDictionary dd = lcc.getDataDictionary();
DependencyManager dm = dd.getDependencyManager();
TransactionController tc = lcc.getTransactionExecute();
/* get the column descriptor for column to be renamed and
* using it's position in the table, set the referenced
* column map of the table indicating which column is being
* renamed. Dependency Manager uses this to find out the
* dependents on the column.
*/
columnDescriptor = td.getColumnDescriptor(oldObjectName);
if (columnDescriptor.isAutoincrement())
columnDescriptor.setAutoinc_create_or_modify_Start_Increment(ColumnDefinitionNode.CREATE_AUTOINCREMENT);
columnPosition = columnDescriptor.getPosition();
FormatableBitSet toRename = new FormatableBitSet(td.getColumnDescriptorList().size() + 1);
toRename.set(columnPosition);
td.setReferencedColumnMap(toRename);
dm.invalidateFor(td, DependencyManager.RENAME, lcc);
// look for foreign key dependency on the column.
constraintDescriptorList = dd.getConstraintDescriptors(td);
for (int index = 0; index < constraintDescriptorList.size(); index++) {
constraintDescriptor = constraintDescriptorList.elementAt(index);
int[] referencedColumns = constraintDescriptor.getReferencedColumns();
int numRefCols = referencedColumns.length;
for (int j = 0; j < numRefCols; j++) {
if ((referencedColumns[j] == columnPosition) && (constraintDescriptor instanceof ReferencedKeyConstraintDescriptor))
dm.invalidateFor(constraintDescriptor, DependencyManager.RENAME, lcc);
}
}
// Drop the column
dd.dropColumnDescriptor(td.getUUID(), oldObjectName, tc);
columnDescriptor.setColumnName(newObjectName);
dd.addDescriptor(columnDescriptor, td, DataDictionary.SYSCOLUMNS_CATALOG_NUM, false, tc);
// Need to do following to reload the cache so that table
// descriptor now has new column name
td = dd.getTableDescriptor(td.getObjectID());
}
use of org.apache.derby.iapi.sql.dictionary.ConstraintDescriptorList in project derby by apache.
the class RenameConstantAction method execGutsRenameTable.
// do necessary work for rename table at execute time.
private void execGutsRenameTable(TableDescriptor td, Activation activation) throws StandardException {
ConstraintDescriptorList constraintDescriptorList;
ConstraintDescriptor constraintDescriptor;
LanguageConnectionContext lcc = activation.getLanguageConnectionContext();
DataDictionary dd = lcc.getDataDictionary();
DependencyManager dm = dd.getDependencyManager();
TransactionController tc = lcc.getTransactionExecute();
dm.invalidateFor(td, DependencyManager.RENAME, lcc);
/* look for foreign key dependency on the table. If found any,
use dependency manager to pass the rename action to the
dependents. */
constraintDescriptorList = dd.getConstraintDescriptors(td);
for (int index = 0; index < constraintDescriptorList.size(); index++) {
constraintDescriptor = constraintDescriptorList.elementAt(index);
if (constraintDescriptor instanceof ReferencedKeyConstraintDescriptor)
dm.invalidateFor(constraintDescriptor, DependencyManager.RENAME, lcc);
}
// Drop the table
dd.dropTableDescriptor(td, sd, tc);
// Change the table name of the table descriptor
td.setTableName(newTableName);
// add the table descriptor with new name
dd.addDescriptor(td, sd, DataDictionary.SYSTABLES_CATALOG_NUM, false, tc);
}
use of org.apache.derby.iapi.sql.dictionary.ConstraintDescriptorList in project derby by apache.
the class DropTableConstantAction method dropAllConstraintDescriptors.
private void dropAllConstraintDescriptors(TableDescriptor td, Activation activation) throws StandardException {
ConstraintDescriptor cd;
ConstraintDescriptorList cdl;
ConstraintDescriptor fkcd;
ConstraintDescriptorList fkcdl;
LanguageConnectionContext lcc = activation.getLanguageConnectionContext();
DataDictionary dd = lcc.getDataDictionary();
DependencyManager dm = dd.getDependencyManager();
TransactionController tc = lcc.getTransactionExecute();
cdl = dd.getConstraintDescriptors(td);
/* The current element will be deleted underneath
* the loop, so we only increment the counter when
* skipping an element. (HACK!)
*/
for (int index = 0; index < cdl.size(); ) {
cd = cdl.elementAt(index);
if (cd instanceof ReferencedKeyConstraintDescriptor) {
index++;
continue;
}
dm.invalidateFor(cd, DependencyManager.DROP_CONSTRAINT, lcc);
dropConstraint(cd, td, activation, lcc, true);
}
/* The current element will be deleted underneath
* the loop. (HACK!)
*/
while (cdl.size() > 0) {
cd = cdl.elementAt(0);
if (SanityManager.DEBUG) {
if (!(cd instanceof ReferencedKeyConstraintDescriptor)) {
SanityManager.THROWASSERT("Constraint descriptor not an instance of " + "ReferencedKeyConstraintDescriptor as expected. Is a " + cd.getClass().getName());
}
}
/*
** Drop the referenced constraint (after we got
** the primary keys) now. Do this prior to
** droping the referenced keys to avoid performing
** a lot of extra work updating the referencedcount
** field of sys.sysconstraints.
**
** Pass in false to dropConstraintsAndIndex so it
** doesn't clear dependencies, we'll do that ourselves.
*/
dropConstraint(cd, td, activation, lcc, false);
/*
** If we are going to cascade, get all the
** referencing foreign keys and zap them first.
*/
if (cascade) {
/*
** Go to the system tables to get the foreign keys
** to be safe
*/
fkcdl = dd.getForeignKeys(cd.getUUID());
/*
** For each FK that references this key, drop
** it.
*/
for (int inner = 0; inner < fkcdl.size(); inner++) {
fkcd = (ConstraintDescriptor) fkcdl.elementAt(inner);
dm.invalidateFor(fkcd, DependencyManager.DROP_CONSTRAINT, lcc);
dropConstraint(fkcd, td, activation, lcc, true);
activation.addWarning(StandardException.newWarning(SQLState.LANG_CONSTRAINT_DROPPED, fkcd.getConstraintName(), fkcd.getTableDescriptor().getName()));
}
}
/*
** Now that we got rid of the fks (if we were cascading), it is
** ok to do an invalidate for.
*/
dm.invalidateFor(cd, DependencyManager.DROP_CONSTRAINT, lcc);
dm.clearDependencies(lcc, cd);
}
}
use of org.apache.derby.iapi.sql.dictionary.ConstraintDescriptorList in project derby by apache.
the class AlterTableConstantAction method dropColumnFromTable.
/**
* Workhorse for dropping a column from a table.
*
* This routine drops a column from a table, taking care
* to properly handle the various related schema objects.
*
* The syntax which gets you here is:
*
* ALTER TABLE tbl DROP [COLUMN] col [CASCADE|RESTRICT]
*
* The keyword COLUMN is optional, and if you don't
* specify CASCADE or RESTRICT, the default is CASCADE
* (the default is chosen in the parser, not here).
*
* If you specify RESTRICT, then the column drop should be
* rejected if it would cause a dependent schema object
* to become invalid.
*
* If you specify CASCADE, then the column drop should
* additionally drop other schema objects which have
* become invalid.
*
* You may not drop the last (only) column in a table.
*
* Schema objects of interest include:
* - views
* - triggers
* - constraints
* - check constraints
* - primary key constraints
* - foreign key constraints
* - unique key constraints
* - not null constraints
* - privileges
* - indexes
* - default values
*
* Dropping a column may also change the column position
* numbers of other columns in the table, which may require
* fixup of schema objects (such as triggers and column
* privileges) which refer to columns by column position number.
*
* Indexes are a bit interesting. The official SQL spec
* doesn't talk about indexes; they are considered to be
* an imlementation-specific performance optimization.
* The current Derby behavior is that:
* - CASCADE/RESTRICT doesn't matter for indexes
* - when a column is dropped, it is removed from any indexes
* which contain it.
* - if that column was the only column in the index, the
* entire index is dropped.
*
* @param columnName the name of the column specfication in the ALTER
* statement-- currently we allow only one.
* @exception StandardException thrown on failure.
*/
private void dropColumnFromTable(String columnName) throws StandardException {
boolean cascade = (behavior == StatementType.DROP_CASCADE);
// drop any generated columns which reference this column
ColumnDescriptorList generatedColumnList = td.getGeneratedColumns();
int generatedColumnCount = generatedColumnList.size();
ArrayList<String> cascadedDroppedColumns = new ArrayList<String>();
for (int i = 0; i < generatedColumnCount; i++) {
ColumnDescriptor generatedColumn = generatedColumnList.elementAt(i);
String[] referencedColumnNames = generatedColumn.getDefaultInfo().getReferencedColumnNames();
int referencedColumnCount = referencedColumnNames.length;
for (int j = 0; j < referencedColumnCount; j++) {
if (columnName.equals(referencedColumnNames[j])) {
String generatedColumnName = generatedColumn.getColumnName();
// we're trying to drop
if (!cascade) {
//
throw StandardException.newException(SQLState.LANG_PROVIDER_HAS_DEPENDENT_OBJECT, dm.getActionString(DependencyManager.DROP_COLUMN), columnName, "GENERATED COLUMN", generatedColumnName);
} else {
cascadedDroppedColumns.add(generatedColumnName);
}
}
}
}
DataDescriptorGenerator ddg = dd.getDataDescriptorGenerator();
int cascadedDrops = cascadedDroppedColumns.size();
int sizeAfterCascadedDrops = td.getColumnDescriptorList().size() - cascadedDrops;
// can NOT drop a column if it is the only one in the table
if (sizeAfterCascadedDrops == 1) {
throw StandardException.newException(SQLState.LANG_PROVIDER_HAS_DEPENDENT_OBJECT, dm.getActionString(DependencyManager.DROP_COLUMN), "THE *LAST* COLUMN " + columnName, "TABLE", td.getQualifiedName());
}
// now drop dependent generated columns
for (int i = 0; i < cascadedDrops; i++) {
String generatedColumnName = cascadedDroppedColumns.get(i);
activation.addWarning(StandardException.newWarning(SQLState.LANG_GEN_COL_DROPPED, generatedColumnName, td.getName()));
//
// We can only recurse 2 levels since a generation clause cannot
// refer to other generated columns.
//
dropColumnFromTable(generatedColumnName);
}
/*
* Cascaded drops of dependent generated columns may require us to
* rebuild the table descriptor.
*/
td = dd.getTableDescriptor(tableId);
ColumnDescriptor columnDescriptor = td.getColumnDescriptor(columnName);
// We already verified this in bind, but do it again
if (columnDescriptor == null) {
throw StandardException.newException(SQLState.LANG_COLUMN_NOT_FOUND_IN_TABLE, columnName, td.getQualifiedName());
}
int size = td.getColumnDescriptorList().size();
droppedColumnPosition = columnDescriptor.getPosition();
FormatableBitSet toDrop = new FormatableBitSet(size + 1);
toDrop.set(droppedColumnPosition);
td.setReferencedColumnMap(toDrop);
dm.invalidateFor(td, (cascade ? DependencyManager.DROP_COLUMN : DependencyManager.DROP_COLUMN_RESTRICT), lcc);
// If column has a default we drop the default and any dependencies
if (columnDescriptor.getDefaultInfo() != null) {
dm.clearDependencies(lcc, columnDescriptor.getDefaultDescriptor(dd));
}
// then we need to drop the system-generated sequence backing it.
if (columnDescriptor.isAutoincrement() && dd.checkVersion(DataDictionary.DD_VERSION_DERBY_10_11, null)) {
DropTableConstantAction.dropIdentitySequence(dd, td, activation);
}
// columns which are used through REFERENCING clause
for (TriggerDescriptor trd : dd.getTriggerDescriptors(td)) {
// If we find that the trigger is dependent on the column being
// dropped because column is part of trigger columns list, then
// we will give a warning or drop the trigger based on whether
// ALTER TABLE DROP COLUMN is RESTRICT or CASCADE. In such a
// case, no need to check if the trigger action columns referenced
// through REFERENCING clause also used the column being dropped.
boolean triggerDroppedAlready = false;
int[] referencedCols = trd.getReferencedCols();
if (referencedCols != null) {
int refColLen = referencedCols.length, j;
boolean changed = false;
for (j = 0; j < refColLen; j++) {
if (referencedCols[j] > droppedColumnPosition) {
// Trigger is not defined on the column being dropped
// but the column position of trigger column is changing
// because the position of the column being dropped is
// before the the trigger column
changed = true;
} else if (referencedCols[j] == droppedColumnPosition) {
// the trigger is defined on the column being dropped
if (cascade) {
trd.drop(lcc);
triggerDroppedAlready = true;
activation.addWarning(StandardException.newWarning(SQLState.LANG_TRIGGER_DROPPED, trd.getName(), td.getName()));
} else {
// otherwsie there would be unexpected behaviors
throw StandardException.newException(SQLState.LANG_PROVIDER_HAS_DEPENDENT_OBJECT, dm.getActionString(DependencyManager.DROP_COLUMN), columnName, "TRIGGER", trd.getName());
}
break;
}
}
// drop column.
if (j == refColLen && changed) {
dd.dropTriggerDescriptor(trd, tc);
for (j = 0; j < refColLen; j++) {
if (referencedCols[j] > droppedColumnPosition)
referencedCols[j]--;
}
trd.setReferencedCols(referencedCols);
dd.addDescriptor(trd, sd, DataDictionary.SYSTRIGGERS_CATALOG_NUM, false, tc);
}
}
// loop above, then move to next trigger
if (triggerDroppedAlready)
continue;
// Column being dropped is not one of trigger columns. Check if
// that column is getting used inside the trigger action through
// REFERENCING clause. This can be tracked only for triggers
// created in 10.7 and higher releases. Derby releases prior to
// that did not keep track of trigger action columns used
// through the REFERENCING clause.
int[] referencedColsInTriggerAction = trd.getReferencedColsInTriggerAction();
if (referencedColsInTriggerAction != null) {
int refColInTriggerActionLen = referencedColsInTriggerAction.length, j;
boolean changedColPositionInTriggerAction = false;
for (j = 0; j < refColInTriggerActionLen; j++) {
if (referencedColsInTriggerAction[j] > droppedColumnPosition) {
changedColPositionInTriggerAction = true;
} else if (referencedColsInTriggerAction[j] == droppedColumnPosition) {
if (cascade) {
trd.drop(lcc);
triggerDroppedAlready = true;
activation.addWarning(StandardException.newWarning(SQLState.LANG_TRIGGER_DROPPED, trd.getName(), td.getName()));
} else {
// we'd better give an error if don't drop it,
throw StandardException.newException(SQLState.LANG_PROVIDER_HAS_DEPENDENT_OBJECT, dm.getActionString(DependencyManager.DROP_COLUMN), columnName, "TRIGGER", trd.getName());
}
break;
}
}
// column has been actually dropped from the table descriptor.
if (j == refColInTriggerActionLen && changedColPositionInTriggerAction) {
dd.dropTriggerDescriptor(trd, tc);
for (j = 0; j < refColInTriggerActionLen; j++) {
if (referencedColsInTriggerAction[j] > droppedColumnPosition)
referencedColsInTriggerAction[j]--;
}
trd.setReferencedColsInTriggerAction(referencedColsInTriggerAction);
dd.addDescriptor(trd, sd, DataDictionary.SYSTRIGGERS_CATALOG_NUM, false, tc);
}
}
}
ConstraintDescriptorList csdl = dd.getConstraintDescriptors(td);
int csdl_size = csdl.size();
ArrayList<ConstantAction> newCongloms = new ArrayList<ConstantAction>();
// we want to remove referenced primary/unique keys in the second
// round. This will ensure that self-referential constraints will
// work OK.
int tbr_size = 0;
ConstraintDescriptor[] toBeRemoved = new ConstraintDescriptor[csdl_size];
// let's go downwards, don't want to get messed up while removing
for (int i = csdl_size - 1; i >= 0; i--) {
ConstraintDescriptor cd = csdl.elementAt(i);
int[] referencedColumns = cd.getReferencedColumns();
int numRefCols = referencedColumns.length, j;
boolean changed = false;
for (j = 0; j < numRefCols; j++) {
if (referencedColumns[j] > droppedColumnPosition)
changed = true;
if (referencedColumns[j] == droppedColumnPosition)
break;
}
if (// column not referenced
j == numRefCols) {
if ((cd instanceof CheckConstraintDescriptor) && changed) {
dd.dropConstraintDescriptor(cd, tc);
for (j = 0; j < numRefCols; j++) {
if (referencedColumns[j] > droppedColumnPosition)
referencedColumns[j]--;
}
((CheckConstraintDescriptor) cd).setReferencedColumnsDescriptor(new ReferencedColumnsDescriptorImpl(referencedColumns));
dd.addConstraintDescriptor(cd, tc);
}
continue;
}
if (!cascade) {
//
throw StandardException.newException(SQLState.LANG_PROVIDER_HAS_DEPENDENT_OBJECT, dm.getActionString(DependencyManager.DROP_COLUMN), columnName, "CONSTRAINT", cd.getConstraintName());
}
if (cd instanceof ReferencedKeyConstraintDescriptor) {
// restrict will raise an error in invalidate if referenced
toBeRemoved[tbr_size++] = cd;
continue;
}
// drop now in all other cases
dm.invalidateFor(cd, DependencyManager.DROP_CONSTRAINT, lcc);
dropConstraint(cd, td, newCongloms, activation, lcc, true);
activation.addWarning(StandardException.newWarning(SQLState.LANG_CONSTRAINT_DROPPED, cd.getConstraintName(), td.getName()));
}
for (int i = tbr_size - 1; i >= 0; i--) {
ConstraintDescriptor cd = toBeRemoved[i];
dropConstraint(cd, td, newCongloms, activation, lcc, false);
activation.addWarning(StandardException.newWarning(SQLState.LANG_CONSTRAINT_DROPPED, cd.getConstraintName(), td.getName()));
if (cascade) {
ConstraintDescriptorList fkcdl = dd.getForeignKeys(cd.getUUID());
for (ConstraintDescriptor fkcd : fkcdl) {
dm.invalidateFor(fkcd, DependencyManager.DROP_CONSTRAINT, lcc);
dropConstraint(fkcd, td, newCongloms, activation, lcc, true);
activation.addWarning(StandardException.newWarning(SQLState.LANG_CONSTRAINT_DROPPED, fkcd.getConstraintName(), fkcd.getTableDescriptor().getName()));
}
}
dm.invalidateFor(cd, DependencyManager.DROP_CONSTRAINT, lcc);
dm.clearDependencies(lcc, cd);
}
/* If there are new backing conglomerates which must be
* created to replace a dropped shared conglomerate
* (where the shared conglomerate was dropped as part
* of a "drop constraint" call above), then create them
* now. We do this *after* dropping all dependent
* constraints because we don't want to waste time
* creating a new conglomerate if it's just going to be
* dropped again as part of another "drop constraint".
*/
createNewBackingCongloms(newCongloms, (long[]) null);
/*
* The work we've done above, specifically the possible
* dropping of primary key, foreign key, and unique constraints
* and their underlying indexes, may have affected the table
* descriptor. By re-reading the table descriptor here, we
* ensure that the compressTable code is working with an
* accurate table descriptor. Without this line, we may get
* conglomerate-not-found errors and the like due to our
* stale table descriptor.
*/
td = dd.getTableDescriptor(tableId);
compressTable();
ColumnDescriptorList tab_cdl = td.getColumnDescriptorList();
// drop the column from syscolumns
dd.dropColumnDescriptor(td.getUUID(), columnName, tc);
ColumnDescriptor[] cdlArray = new ColumnDescriptor[size - columnDescriptor.getPosition()];
//
for (int i = columnDescriptor.getPosition(), j = 0; i < size; i++, j++) {
ColumnDescriptor cd = tab_cdl.elementAt(i);
dd.dropColumnDescriptor(td.getUUID(), cd.getColumnName(), tc);
cd.setPosition(i);
if (cd.isAutoincrement()) {
cd.setAutoinc_create_or_modify_Start_Increment(ColumnDefinitionNode.CREATE_AUTOINCREMENT);
}
cdlArray[j] = cd;
}
dd.addDescriptorArray(cdlArray, td, DataDictionary.SYSCOLUMNS_CATALOG_NUM, false, tc);
// By this time, the column has been removed from the table descriptor.
// Now, go through all the triggers and regenerate their trigger action
// SPS and rebind the generated trigger action sql. If the trigger
// action is using the dropped column, it will get detected here. If
// not, then we will have generated the internal trigger action sql
// which matches the trigger action sql provided by the user.
//
// eg of positive test case
// create table atdc_16_tab1 (a1 integer, b1 integer, c1 integer);
// create table atdc_16_tab2 (a2 integer, b2 integer, c2 integer);
// create trigger atdc_16_trigger_1
// after update of b1 on atdc_16_tab1
// REFERENCING NEW AS newt
// for each row
// update atdc_16_tab2 set c2 = newt.c1
// The internal representation for the trigger action before the column
// is dropped is as follows
// update atdc_16_tab2 set c2 =
// org.apache.derby.iapi.db.Factory::getTriggerExecutionContext().
// getONewRow().getInt(3)
// After the drop column shown as below
// alter table DERBY4998_SOFT_UPGRADE_RESTRICT drop column c11
// The above internal representation of tigger action sql is not
// correct anymore because column position of c1 in atdc_16_tab1 has
// now changed from 3 to 2. Following while loop will regenerate it and
// change it to as follows
// update atdc_16_tab2 set c2 =
// org.apache.derby.iapi.db.Factory::getTriggerExecutionContext().
// getONewRow().getInt(2)
//
// We could not do this before the actual column drop, because the
// rebind would have still found the column being dropped in the
// table descriptor and hence use of such a column in the trigger
// action rebind would not have been caught.
// For the table on which ALTER TABLE is getting performed, find out
// all the SPSDescriptors that use that table as a provider. We are
// looking for SPSDescriptors that have been created internally for
// trigger action SPSes. Through those SPSDescriptors, we will be
// able to get to the triggers dependent on the table being altered
// Following will get all the dependent objects that are using
// ALTER TABLE table as provider
List<DependencyDescriptor> depsOnAlterTableList = dd.getProvidersDescriptorList(td.getObjectID().toString());
for (DependencyDescriptor depOnAT : depsOnAlterTableList) {
// Go through all the dependent objects on the table being altered
DependableFinder dependent = depOnAT.getDependentFinder();
// stored prepared statement.
if (dependent.getSQLObjectType().equals(Dependable.STORED_PREPARED_STATEMENT)) {
// Look for all the dependent objects that are using this
// stored prepared statement as provider. We are only
// interested in dependents that are triggers.
List<DependencyDescriptor> depsTrigger = dd.getProvidersDescriptorList(depOnAT.getUUID().toString());
for (DependencyDescriptor depsTriggerDesc : depsTrigger) {
DependableFinder providerIsTrigger = depsTriggerDesc.getDependentFinder();
// it is a trigger
if (providerIsTrigger.getSQLObjectType().equals(Dependable.TRIGGER)) {
// Drop and recreate the trigger after regenerating
// it's trigger action plan. If the trigger action
// depends on the column being dropped, it will be
// caught here.
TriggerDescriptor trdToBeDropped = dd.getTriggerDescriptor(depsTriggerDesc.getUUID());
// First check for dependencies in the trigger's WHEN
// clause, if there is one.
UUID whenClauseId = trdToBeDropped.getWhenClauseId();
boolean gotDropped = false;
if (whenClauseId != null) {
gotDropped = columnDroppedAndTriggerDependencies(trdToBeDropped, whenClauseId, true, cascade, columnName);
}
// dependencies.
if (!gotDropped) {
columnDroppedAndTriggerDependencies(trdToBeDropped, trdToBeDropped.getActionId(), false, cascade, columnName);
}
}
}
}
}
// Adjust the column permissions rows in SYSCOLPERMS to reflect the
// changed column positions due to the dropped column:
dd.updateSYSCOLPERMSforDropColumn(td.getUUID(), tc, columnDescriptor);
// remove column descriptor from table descriptor. this fixes up the
// list in case we were called recursively in order to cascade-drop a
// dependent generated column.
tab_cdl.remove(td.getColumnDescriptor(columnName));
}
use of org.apache.derby.iapi.sql.dictionary.ConstraintDescriptorList in project derby by apache.
the class AlterTableConstantAction method executeConstantActionBody.
/**
* This is the guts of the Execution-time logic for ALTER TABLE.
*
* @see ConstantAction#executeConstantAction
*
* @exception StandardException Thrown on failure
*/
private void executeConstantActionBody(Activation activation) throws StandardException {
// Save references to the main structures we need.
this.activation = activation;
lcc = activation.getLanguageConnectionContext();
dd = lcc.getDataDictionary();
dm = dd.getDependencyManager();
tc = lcc.getTransactionExecute();
int numRows = 0;
boolean tableScanned = false;
if (compressTable || truncateTable) {
DeferredConstraintsMemory.compressOrTruncate(lcc, tableId, tableName);
}
// tables to do the compression is done later in this method.
if (compressTable) {
if (purge || defragment || truncateEndOfTable) {
td = dd.getTableDescriptor(tableId);
if (td == null) {
throw StandardException.newException(SQLState.LANG_TABLE_NOT_FOUND_DURING_EXECUTION, tableName);
}
// made larger by the previous purge/defragment pass.
if (purge)
purgeRows(tc);
if (defragment)
defragmentRows(tc);
if (truncateEndOfTable)
truncateEnd(tc);
return;
}
}
if (updateStatistics) {
updateStatistics();
return;
}
if (dropStatistics) {
dropStatistics();
return;
}
/*
** Inform the data dictionary that we are about to write to it.
** There are several calls to data dictionary "get" methods here
** that might be done in "read" mode in the data dictionary, but
** it seemed safer to do this whole operation in "write" mode.
**
** We tell the data dictionary we're done writing at the end of
** the transaction.
*/
dd.startWriting(lcc);
// older version (or at target) has to get td first, potential deadlock
if (tableConglomerateId == 0) {
td = dd.getTableDescriptor(tableId);
if (td == null) {
throw StandardException.newException(SQLState.LANG_TABLE_NOT_FOUND_DURING_EXECUTION, tableName);
}
tableConglomerateId = td.getHeapConglomerateId();
}
lockTableForDDL(tc, tableConglomerateId, true);
td = dd.getTableDescriptor(tableId);
if (td == null) {
throw StandardException.newException(SQLState.LANG_TABLE_NOT_FOUND_DURING_EXECUTION, tableName);
}
if (truncateTable)
dm.invalidateFor(td, DependencyManager.TRUNCATE_TABLE, lcc);
else
dm.invalidateFor(td, DependencyManager.ALTER_TABLE, lcc);
// Save the TableDescriptor off in the Activation
activation.setDDLTableDescriptor(td);
/*
** If the schema descriptor is null, then we must have just read
** ourselves in. So we will get the corresponding schema descriptor
** from the data dictionary.
*/
if (sd == null) {
sd = getAndCheckSchemaDescriptor(dd, schemaId, "ALTER TABLE");
}
/* Prepare all dependents to invalidate. (This is their chance
* to say that they can't be invalidated. For example, an open
* cursor referencing a table/view that the user is attempting to
* alter.) If no one objects, then invalidate any dependent objects.
*/
if (truncateTable)
dm.invalidateFor(td, DependencyManager.TRUNCATE_TABLE, lcc);
else
dm.invalidateFor(td, DependencyManager.ALTER_TABLE, lcc);
// Are we working on columns?
if (columnInfo != null) {
boolean tableNeedsScanning = false;
/* for each new column, see if the user is adding a non-nullable
* column. This is only allowed on an empty table.
*/
for (int ix = 0; ix < columnInfo.length; ix++) {
/* Is this new column non-nullable?
* If so, it can only be added to an
* empty table if it does not have a default value.
* We need to scan the table to find out how many rows
* there are.
*/
if ((columnInfo[ix].action == ColumnInfo.CREATE) && !(columnInfo[ix].dataType.isNullable()) && (columnInfo[ix].defaultInfo == null) && (columnInfo[ix].autoincInc == 0)) {
tableNeedsScanning = true;
}
}
// Scan the table if necessary
if (tableNeedsScanning) {
numRows = getSemiRowCount(tc);
// Don't allow add of non-nullable column to non-empty table
if (numRows > 0) {
throw StandardException.newException(SQLState.LANG_ADDING_NON_NULL_COLUMN_TO_NON_EMPTY_TABLE, td.getQualifiedName());
}
tableScanned = true;
}
// for each related column, stuff system.column
for (int ix = 0; ix < columnInfo.length; ix++) {
if (columnInfo[ix].action == ColumnInfo.CREATE) {
addNewColumnToTable(ix);
} else if (columnInfo[ix].action == ColumnInfo.MODIFY_COLUMN_DEFAULT_RESTART || columnInfo[ix].action == ColumnInfo.MODIFY_COLUMN_DEFAULT_INCREMENT || columnInfo[ix].action == ColumnInfo.MODIFY_COLUMN_DEFAULT_CYCLE || columnInfo[ix].action == ColumnInfo.MODIFY_COLUMN_DEFAULT_VALUE) {
modifyColumnDefault(ix);
} else if (columnInfo[ix].action == ColumnInfo.MODIFY_COLUMN_TYPE) {
modifyColumnType(ix);
} else if (columnInfo[ix].action == ColumnInfo.MODIFY_COLUMN_CONSTRAINT) {
modifyColumnConstraint(columnInfo[ix].name, true);
} else if (columnInfo[ix].action == ColumnInfo.MODIFY_COLUMN_CONSTRAINT_NOT_NULL) {
if (!tableScanned) {
tableScanned = true;
numRows = getSemiRowCount(tc);
}
// check that the data in the column is not null
String[] colNames = new String[1];
colNames[0] = columnInfo[ix].name;
boolean[] nullCols = new boolean[1];
/* note validateNotNullConstraint returns true if the
* column is nullable
*/
if (validateNotNullConstraint(colNames, nullCols, numRows, lcc, SQLState.LANG_NULL_DATA_IN_NON_NULL_COLUMN)) {
/* nullable column - modify it to be not null
* This is O.K. at this point since we would have
* thrown an exception if any data was null
*/
modifyColumnConstraint(columnInfo[ix].name, false);
}
} else if (columnInfo[ix].action == ColumnInfo.DROP) {
dropColumnFromTable(columnInfo[ix].name);
} else if ((columnInfo[ix].action == ColumnInfo.MODIFY_COLUMN_GENERATED_ALWAYS) || (columnInfo[ix].action == ColumnInfo.MODIFY_COLUMN_GENERATED_BY_DEFAULT)) {
modifyIdentityState(ix);
} else if (SanityManager.DEBUG) {
SanityManager.THROWASSERT("Unexpected action in AlterTableConstantAction");
}
}
}
// adjust dependencies on user defined types
adjustUDTDependencies(lcc, dd, td, columnInfo, false);
/* Create/Drop/alter any constraints */
if (constraintActions != null) {
for (int conIndex = 0; conIndex < constraintActions.length; conIndex++) {
ConstraintConstantAction cca = constraintActions[conIndex];
boolean isCheckInitiallyDeferred = false;
if (cca instanceof CreateConstraintConstantAction) {
final CreateConstraintConstantAction ccca = (CreateConstraintConstantAction) cca;
int constraintType = ccca.getConstraintType();
isCheckInitiallyDeferred = (constraintType == DataDictionary.CHECK_CONSTRAINT) && ccca.isInitiallyDeferred();
/* Some constraint types require special checking:
* Check - table must be empty, for now
* Primary Key - table cannot already have a primary key
*/
switch(constraintType) {
case DataDictionary.PRIMARYKEY_CONSTRAINT:
// Check to see if a constraint of the same type
// already exists
ConstraintDescriptorList cdl = dd.getConstraintDescriptors(td);
if (cdl.getPrimaryKey() != null) {
throw StandardException.newException(SQLState.LANG_ADD_PRIMARY_KEY_FAILED1, td.getQualifiedName());
}
if (!tableScanned) {
tableScanned = true;
numRows = getSemiRowCount(tc);
}
break;
case DataDictionary.CHECK_CONSTRAINT:
if (!tableScanned) {
tableScanned = true;
numRows = getSemiRowCount(tc);
}
if (isCheckInitiallyDeferred) {
// Need to do this early to get UUID
// assigned
constraintActions[conIndex].executeConstantAction(activation);
}
if (numRows > 0) {
/*
** We are assuming that there will only be one
** check constraint that we are adding, so it
** is ok to do the check now rather than try
** to lump together several checks.
*/
ConstraintConstantAction.validateConstraint(cca.getConstraintName(), ((CreateConstraintConstantAction) cca).getConstraintText(), cca.getConstraintId(), td, lcc, true, isCheckInitiallyDeferred);
}
break;
}
} else {
if (SanityManager.DEBUG) {
if (!(cca instanceof DropConstraintConstantAction || cca instanceof AlterConstraintConstantAction)) {
SanityManager.THROWASSERT("constraintActions[" + conIndex + "] expected to be instanceof " + "DropConstraintConstantAction not " + cca.getClass().getName());
}
}
}
if (!isCheckInitiallyDeferred) {
constraintActions[conIndex].executeConstantAction(activation);
}
// else it is done early, see above.
}
}
// Are we changing the lock granularity?
if (lockGranularity != '\0') {
if (SanityManager.DEBUG) {
if (lockGranularity != 'T' && lockGranularity != 'R') {
SanityManager.THROWASSERT("lockGranularity expected to be 'T'or 'R', not " + lockGranularity);
}
}
// update the TableDescriptor
td.setLockGranularity(lockGranularity);
// update the DataDictionary
dd.updateLockGranularity(td, sd, lockGranularity, tc);
}
// Are we doing a compress table?
if (compressTable) {
compressTable();
}
// Are we doing a truncate table?
if (truncateTable) {
truncateTable();
}
}
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