/*
* TableDDLCommandList takes in a relationId, and returns the list of DDL
* command needed to reconstruct the relation. These DDL commands are all
* palloced; and include the table's schema definition, optional column
* storage and statistics definitions, and index and constraint defitions.
*/
List *
TableDDLCommandList(Oid relationId)
{
List *tableDDLCommandList = NIL;
char *tableSchemaDef = NULL;
char *tableColumnOptionsDef = NULL;
Relation pgIndex = NULL;
SysScanDesc scanDescriptor = NULL;
ScanKeyData scanKey[1];
int scanKeyCount = 1;
HeapTuple heapTuple = NULL;
/* fetch table schema and column option definitions */
tableSchemaDef = pg_shard_get_tableschemadef_string(relationId);
tableColumnOptionsDef = pg_shard_get_tablecolumnoptionsdef_string(relationId);
tableDDLCommandList = lappend(tableDDLCommandList, tableSchemaDef);
if (tableColumnOptionsDef != NULL)
{
tableDDLCommandList = lappend(tableDDLCommandList, tableColumnOptionsDef);
}
/* open system catalog and scan all indexes that belong to this table */
pgIndex = heap_open(IndexRelationId, AccessShareLock);
ScanKeyInit(&scanKey[0], Anum_pg_index_indrelid,
BTEqualStrategyNumber, F_OIDEQ, relationId);
scanDescriptor = systable_beginscan(pgIndex,
IndexIndrelidIndexId, true, /* indexOK */
SnapshotSelf, scanKeyCount, scanKey);
heapTuple = systable_getnext(scanDescriptor);
while (HeapTupleIsValid(heapTuple))
{
Form_pg_index indexForm = (Form_pg_index) GETSTRUCT(heapTuple);
Oid indexId = indexForm->indexrelid;
bool isConstraint = false;
char *statementDef = NULL;
/*
* A primary key index is always created by a constraint statement.
* A unique key index is created by a constraint if and only if the
* index has a corresponding constraint entry in pg_depend. Any other
* index form is never associated with a constraint.
*/
if (indexForm->indisprimary)
{
isConstraint = true;
}
else if (indexForm->indisunique)
{
Oid constraintId = get_index_constraint(indexId);
isConstraint = OidIsValid(constraintId);
}
else
{
isConstraint = false;
}
/* get the corresponding constraint or index statement */
if (isConstraint)
{
Oid constraintId = get_index_constraint(indexId);
Assert(constraintId != InvalidOid);
statementDef = pg_get_constraintdef_string(constraintId);
}
else
{
statementDef = pg_get_indexdef_string(indexId);
}
/* append found constraint or index definition to the list */
tableDDLCommandList = lappend(tableDDLCommandList, statementDef);
/* if table is clustered on this index, append definition to the list */
if (indexForm->indisclustered)
{
char *clusteredDef = pg_shard_get_indexclusterdef_string(indexId);
Assert(clusteredDef != NULL);
tableDDLCommandList = lappend(tableDDLCommandList, clusteredDef);
}
heapTuple = systable_getnext(scanDescriptor);
}
/* clean up scan and close system catalog */
systable_endscan(scanDescriptor);
heap_close(pgIndex, AccessShareLock);
return tableDDLCommandList;
}
/*
* GetTableIndexAndConstraintCommands returns the list of DDL commands to
* (re)create indexes and constraints for a given table.
*/
List *
GetTableIndexAndConstraintCommands(Oid relationId)
{
List *indexDDLEventList = NIL;
Relation pgIndex = NULL;
SysScanDesc scanDescriptor = NULL;
ScanKeyData scanKey[1];
int scanKeyCount = 1;
HeapTuple heapTuple = NULL;
/*
* Set search_path to NIL so that all objects outside of pg_catalog will be
* schema-prefixed. pg_catalog will be added automatically when we call
* PushOverrideSearchPath(), since we set addCatalog to true;
*/
OverrideSearchPath *overridePath = GetOverrideSearchPath(CurrentMemoryContext);
overridePath->schemas = NIL;
overridePath->addCatalog = true;
PushOverrideSearchPath(overridePath);
/* open system catalog and scan all indexes that belong to this table */
pgIndex = heap_open(IndexRelationId, AccessShareLock);
ScanKeyInit(&scanKey[0], Anum_pg_index_indrelid,
BTEqualStrategyNumber, F_OIDEQ, relationId);
scanDescriptor = systable_beginscan(pgIndex,
IndexIndrelidIndexId, true, /* indexOK */
NULL, scanKeyCount, scanKey);
heapTuple = systable_getnext(scanDescriptor);
while (HeapTupleIsValid(heapTuple))
{
Form_pg_index indexForm = (Form_pg_index) GETSTRUCT(heapTuple);
Oid indexId = indexForm->indexrelid;
bool isConstraint = false;
char *statementDef = NULL;
/*
* A primary key index is always created by a constraint statement.
* A unique key index or exclusion index is created by a constraint
* if and only if the index has a corresponding constraint entry in pg_depend.
* Any other index form is never associated with a constraint.
*/
if (indexForm->indisprimary)
{
isConstraint = true;
}
else if (indexForm->indisunique || indexForm->indisexclusion)
{
Oid constraintId = get_index_constraint(indexId);
isConstraint = OidIsValid(constraintId);
}
else
{
isConstraint = false;
}
/* get the corresponding constraint or index statement */
if (isConstraint)
{
Oid constraintId = get_index_constraint(indexId);
Assert(constraintId != InvalidOid);
statementDef = pg_get_constraintdef_command(constraintId);
}
else
{
statementDef = pg_get_indexdef_string(indexId);
}
/* append found constraint or index definition to the list */
indexDDLEventList = lappend(indexDDLEventList, statementDef);
/* if table is clustered on this index, append definition to the list */
if (indexForm->indisclustered)
{
char *clusteredDef = pg_get_indexclusterdef_string(indexId);
Assert(clusteredDef != NULL);
indexDDLEventList = lappend(indexDDLEventList, clusteredDef);
}
heapTuple = systable_getnext(scanDescriptor);
}
/* clean up scan and close system catalog */
systable_endscan(scanDescriptor);
heap_close(pgIndex, AccessShareLock);
/* revert back to original search_path */
PopOverrideSearchPath();
return indexDDLEventList;
}
