Wiki / Configuration Parameters
cursor_tuple_fraction
Sets the planner's estimate of the fraction of a cursor's rows that will be retrieved. The default is 0.1. Smaller values of this setting bias the planner towards using “fast start” plans for cursors, which will retrieve the first few rows quickly while perhaps taking a long time to fetch all rows. Larger values put more emphasis on the total estimated time. At the maximum setting of 1.0, cursors are planned exactly like regular queries, considering only the total estimated time and not how soon the first rows might be delivered.
English manual coverage begins with PostgreSQL 7.4. Source history and runtime observations have their own recorded version boundaries.
Reading PG 18·Select a recorded version
- boot val
- 0.1
- category
- Query Tuning / Other Planner Options
- context
- user
- documented
- true
- enumvals
- Unknown
- extra desc
- Unknown
- lang
- en
- max val
- 1
- metadata version
- 18
- min val
- 0
- name
- cursor_tuple_fraction
- short desc
- Sets the planner's estimate of the fraction of a cursor's rows that will be retrieved.
- source
- pg-settings-source-snapshot
- unit
- Unknown
- vartype
- real
Definition PG 18
Sets the planner's estimate of the fraction of a cursor's rows that will be retrieved. The default is 0.1. Smaller values of this setting bias the planner towards using “fast start” plans for cursors, which will retrieve the first few rows quickly while perhaps taking a long time to fetch all rows. Larger values put more emphasis on the total estimated time. At the maximum setting of 1.0, cursors are planned exactly like regular queries, considering only the total estimated time and not how soon the first rows might be delivered.
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center · PostgreSQL 18 · wiki-repair-20261023:cbd521eed95100bc39d65dd91ba3b9641f8b42f3441cafbef5467fb28299ae6d
Text language: en · wiki-repair-20261023:cbd521eed95100bc39d65dd91ba3b9641f8b42f3441cafbef5467fb28299ae6d