PG_HASHBUCKET
PG_HASHBUCKET records hash bucket information.
Table 1 PG_HASHBUCKET columns
Name
|
Type
|
Description
|
|---|
oid
|
oid
|
Row identifier (hidden attribute, which must be specified)
|
bucketid
|
oid
|
Hash value calculated for a bucket vector. The hash value can be used to accelerate the search for a bucket vector.
|
bucketcnt
|
integer
|
Number of shards
|
bucketmapsize
|
integer
|
Total number of shards on all DNs
|
bucketref
|
integer
|
Reserved column with 1 as its default value
|
bucketvector
|
oidvector_extend
|
Records all bucket IDs contained in the bucket information in this row. A unique index is created in this column. Tables with the same bucket ID share the PG_HASHBUCKET data in the same row.
|