A tabela SYSKEYTGTDISTSTATS contém zero ou mais linhas por partição para o primeiro destino de chave de um índice secundário particionado por dados.
Linhas são inseridas quando RUNSTATS examina um índice secundário particionado por dados.
Nenhuma linha será inserida se o índice for um índice secundário. As linhas nesta tabela podem ser inseridas, atualizadas e excluídas.
Importante:
Tenha cuidado ao emitir instruções SQL ou usar ferramentas para atualizar os valores das estatísticas nas tabelas do catálogo.
Se essas atualizações introduzirem dados inválidos, resultados imprevisíveis podem ocorrer, incluindo abends para RUNSTATS e outros utilitários.
Se esses problemas ocorrerem, você pode executar o utilitário RUNSTATS e coletar estatísticas no nível do espaço de tabela para resolver os problemas, na maioria
dos casos.
The SYSKEYTGTDISTSTATS table contains zero or more rows per partition for the first key-target of a data-partitioned secondary index.
Rows are inserted when RUNSTATS scans a data-partitioned secondary index.
No row is inserted if the index is a secondary index. Rows in this table can be inserted, updated, and deleted.
Important:
Use care when issuing SQL statements or using tools to update statistics values in catalog tables.
If such updates introduce invalid data, unpredictable results can occur, including abends for RUNSTATS and other utilities.
If such problems occur, you can run the RUNSTATS utility and collect statistics at the table space level to resolve the problems, in most cases.
| Column name |
Data type |
Description |
Use |
| STATSTIME |
TIMESTAMP
NOT NULL
WITH DEFAULT |
If RUNSTATS or another utility with inline statistics updated the statistics, the date and time when the last utility invocation updated the statistics.
The default value is '0001-01-01-00.00.00.000000'.
The default value indicates that statistics were not collected.
This is an updatable column. |
G |
| IBMREQD |
CHAR(1)
NOT NULL |
A value of Y indicates that the row came from the basic machine-readable material (MRM) tape.
For all other values, see Release dependency indicators.
The value in this field is not a reliable indicator of release dependencies. |
G |
| PARTITION |
SMALLINT
NOT NULL |
The partition number of the table space that contains the index in which the key is defined. |
G |
| IXSCHEMA |
VARCHAR(128)
NOT NULL |
The qualifier of the index. |
G |
| IXNAME |
VARCHAR(128)
NOT NULL |
The name of the index. |
G |
| KEYSEQ |
SMALLINT
NOT NULL |
Numeric position of the key-target in the index. |
G |
| KEYVALUE |
VARCHAR(2000)
NOT NULL
WITH DEFAULT
FOR BIT DATA |
KEYVALUE contains the data of a frequently occurring value.
If the value has a non-character data type, the data might not be printable. |
S |
| TYPE |
CHAR(1)
NOT NULL
WITH DEFAULT 'F' |
The type of statistics that are gathered:
- C
- Cardinality
- F
- Frequent value
- N
- Non-padded frequent value
- H
- Histogram statistics
|
G |
| CARDF |
FLOAT
NOT NULL
WITH DEFAULT -1 |
When TYPE='C', CARDF contains the number of distinct values for the key group.
When TYPE='H', CARDF contains the number of distinct values for the key group in the quantile that is in QUANTILENO. |
S |
| KEYGROUPKEYNO |
VARCHAR(254)
NOT NULL
WITH DEFAULT |
Identifies the set of keys that are associated with the statistics.
If the statistics are only associated with a single key, KEYGROUPKEYNO contains a zero length value.
Otherwise, KEYGROUPKEYNO contains an array of SMALLINT key numbers that have a dimension that is equal to the value in NUMKEYS. |
S |
| NUMKEYS |
SMALLINT
NOT NULL
WITH DEFAULT |
Identifies the number of keys that are associated with the statistics. |
G |
| FREQUENCYF |
FLOAT
NOT NULL
WITH DEFAULT -1 |
When TYPE='F' or 'N', FREQUENCYF contains the percentage of entries in the index that have the value that is specified in KEYVALUE when the number
of entries is multiplied by 100.
For example, a value of '1' indicates 100 percent.
A value of '.153' indicates 15.3 percent.
When TYPE='H', FREQUENCYF contains the percentage of entries in the index that have a value that is in the range of the quantile that is indicated in QUALTILENO. |
G |
| QUANTILENO |
SMALLINT
NOT NULL
WITH DEFAULT -1 |
QUANTILENO contains an ordinary sequence number of a quantile in the whole consecutive value range, from low to high. |
G |
| LOWVALUE |
VARCHAR(2000)
NOT NULL
WITH DEFAULT
FOR BIT DATA |
When TYPE='H', LOWVALUE is the lower bound for the quantile that is indicated in QUANTILENO. LOWVALUE is not used if TYPE does not equal 'H'. |
G |
| HIGHVALUE |
VARCHAR(2000)
NOT NULL
WITH DEFAULT
FOR BIT DATA |
When TYPE='H', HIGHVALUE is the upper bound for the quantile that is indicated in QUANTILENO. HIGHVALUE is not used if TYPE does not equal 'H'. |
G |
| — |
VARCHAR(1000) |
Internal use only. |
I |
