diff options
Diffstat (limited to 'src/include/nodes/parsenodes.h')
| -rw-r--r-- | src/include/nodes/parsenodes.h | 48 |
1 files changed, 28 insertions, 20 deletions
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h index 4b8727e9193..8720e713c42 100644 --- a/src/include/nodes/parsenodes.h +++ b/src/include/nodes/parsenodes.h @@ -755,7 +755,10 @@ typedef struct XmlSerialize /* Partitioning related definitions */ /* - * PartitionElem - a column in the partition key + * PartitionElem - parse-time representation of a single partition key + * + * expr can be either a raw expression tree or a parse-analyzed expression. + * We don't store these on-disk, though. */ typedef struct PartitionElem { @@ -768,7 +771,9 @@ typedef struct PartitionElem } PartitionElem; /* - * PartitionSpec - partition key specification + * PartitionSpec - parse-time representation of a partition key specification + * + * This represents the key space we will be partitioning on. */ typedef struct PartitionSpec { @@ -778,52 +783,55 @@ typedef struct PartitionSpec int location; /* token location, or -1 if unknown */ } PartitionSpec; +/* Internal codes for partitioning strategies */ #define PARTITION_STRATEGY_LIST 'l' #define PARTITION_STRATEGY_RANGE 'r' /* * PartitionBoundSpec - a partition bound specification + * + * This represents the portion of the partition key space assigned to a + * particular partition. These are stored on disk in pg_class.relpartbound. */ typedef struct PartitionBoundSpec { NodeTag type; - char strategy; + char strategy; /* see PARTITION_STRATEGY codes above */ - /* List partition values */ - List *listdatums; + /* Partitioning info for LIST strategy: */ + List *listdatums; /* List of Consts (or A_Consts in raw tree) */ - /* - * Range partition lower and upper bounds; each member of the lists is a - * PartitionRangeDatum (see below). - */ - List *lowerdatums; - List *upperdatums; + /* Partitioning info for RANGE strategy: */ + List *lowerdatums; /* List of PartitionRangeDatums */ + List *upperdatums; /* List of PartitionRangeDatums */ - int location; + int location; /* token location, or -1 if unknown */ } PartitionBoundSpec; /* - * PartitionRangeDatum + * PartitionRangeDatum - can be either a value or UNBOUNDED + * + * "value" is an A_Const in raw grammar output, a Const after analysis */ typedef struct PartitionRangeDatum { NodeTag type; - bool infinite; - Node *value; + bool infinite; /* true if UNBOUNDED */ + Node *value; /* null if UNBOUNDED */ - int location; + int location; /* token location, or -1 if unknown */ } PartitionRangeDatum; /* - * PartitionCmd - ALTER TABLE partition commands + * PartitionCmd - info for ALTER TABLE ATTACH/DETACH PARTITION commands */ typedef struct PartitionCmd { NodeTag type; - RangeVar *name; - Node *bound; + RangeVar *name; /* name of partition to attach/detach */ + PartitionBoundSpec *bound; /* FOR VALUES, if attaching */ } PartitionCmd; /**************************************************************************** @@ -1969,7 +1977,7 @@ typedef struct CreateStmt List *tableElts; /* column definitions (list of ColumnDef) */ List *inhRelations; /* relations to inherit from (list of * inhRelation) */ - Node *partbound; /* FOR VALUES clause */ + PartitionBoundSpec *partbound; /* FOR VALUES clause */ PartitionSpec *partspec; /* PARTITION BY clause */ TypeName *ofTypename; /* OF typename */ List *constraints; /* constraints (list of Constraint nodes) */ |