![]() When set to a positive value, ANALYZE will assume that the column contains exactly the specified number of distinct nonnull values. n_distinct affects the statistics for the table itself, while n_distinct_inherited affects the statistics gathered for the table plus its inheritance children. PostgreSQLs day-time interval format (e.g. Currently, the only defined per-attribute options are n_distinct and n_distinct_inherited, which override the number-of-distinct-values estimates made by subsequent ANALYZE operations. exist, and unavailable if the object exists but is not available. This form sets or resets per-attribute options. SET STATISTICS acquires a SHARE UPDATE EXCLUSIVE lock. For more information on the use of statistics by the PostgreSQL query planner, refer to Section 14.2. The target can be set in the range 0 to 10000 alternatively, set it to -1 to revert to using the system default statistics target ( default_statistics_target). This form sets the per-column statistics-gathering target for subsequent ANALYZE operations. Otherwise it is created in the current schema. If a schema name is given then the sequence is created in the specified schema. The generator will be owned by the user issuing the command. This involves creating and initializing a new special single-row table with the name name. sequence_option is an option supported by ALTER SEQUENCE such as INCREMENT BY. CREATE SEQUENCE creates a new sequence number generator. These forms alter the sequence that underlies an existing identity column. Each item can hold SQL scalar values, with an additional SQL/JSON. To provide native support for JSON data types within the SQL environment, PostgreSQL implements the SQL/JSON data model. If DROP IDENTITY IF EXISTS is specified and the column is not an identity column, no error is thrown. This section describes: functions and operators for processing and creating JSON data. Like SET DEFAULT, these forms only affect the behavior of subsequent INSERT and UPDATE commands they do not cause rows already in the table to change. These forms change whether a column is an identity column or change the generation attribute of an existing identity column. RENAME CONSTRAINT constraint_name TO new_constraint_nameĪLTER TABLE ALL IN TABLESPACE name ]ĪTTACH PARTITION partition_name AS IDENTITY
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