diff --git a/doc/src/sgml/perform.sgml b/doc/src/sgml/perform.sgml index 1b8e442b0b..a31d3aa5ca 100644 --- a/doc/src/sgml/perform.sgml +++ b/doc/src/sgml/perform.sgml @@ -1,5 +1,5 @@ @@ -603,7 +603,7 @@ SELECT * FROM a, b, c WHERE a.id = b.id AND b.ref = c.id; PostgreSQL planner will switch from exhaustive search to a genetic probabilistic search through a limited number of possibilities. (The switch-over threshold is - set by the geqo_threshold run-time + set by the GEQO_THRESHOLD run-time parameter.) The genetic search takes less time, but it won't necessarily find the best possible plan. diff --git a/doc/src/sgml/plpgsql.sgml b/doc/src/sgml/plpgsql.sgml index e9573736ab..945d1d86dc 100644 --- a/doc/src/sgml/plpgsql.sgml +++ b/doc/src/sgml/plpgsql.sgml @@ -1,5 +1,5 @@ @@ -1350,7 +1350,7 @@ SELECT * FROM some_func(); allow users to allow users to define set-returning functions that do not have this limitation. Currently, the point at which data begins being written to disk is controlled by the - sort_mem configuration variable. Administrators + SORT_MEM configuration variable. Administrators who have sufficient memory to store larger result sets in memory should consider increasing this parameter. diff --git a/doc/src/sgml/ref/analyze.sgml b/doc/src/sgml/ref/analyze.sgml index f0be5af1db..cf472d4a0e 100644 --- a/doc/src/sgml/ref/analyze.sgml +++ b/doc/src/sgml/ref/analyze.sgml @@ -1,5 +1,5 @@ @@ -28,10 +28,10 @@ ANALYZE [ VERBOSE ] [ table [ (Description - ANALYZE collects statistics about the contents of - tables in the database, and stores the results in - the system table pg_statistic. Subsequently, - the query planner uses the statistics to help determine the most efficient + ANALYZE collects statistics about the contents + of tables in the database, and stores the results in the system + table pg_statistic. Subsequently, the query + planner uses these statistics to help determine the most efficient execution plans for queries. @@ -90,49 +90,56 @@ ANALYZE [ VERBOSE ] [ table [ ( - Unlike VACUUM FULL, - ANALYZE requires - only a read lock on the target table, so it can run in parallel with - other activity on the table. + Unlike VACUUM FULL, ANALYZE + requires only a read lock on the target table, so it can run in + parallel with other activity on the table. - For large tables, ANALYZE takes a random sample of the - table contents, rather than examining every row. This allows even very - large tables to be analyzed in a small amount of time. Note, however, - that the statistics are only approximate, and will change slightly each - time ANALYZE is run, even if the actual table contents - did not change. This may result in small changes in the planner's - estimated costs shown by EXPLAIN. + The statistics collected by ANALYZE usually + include a list of some of the most common values in each column and + a histogram showing the approximate data distribution in each + column. One or both of these may be omitted if + ANALYZE deems them uninteresting (for example, + in a unique-key column, there are no common values) or if the + column data type does not support the appropriate operators. There + is more information about the statistics in . - The collected statistics usually include a list of some of the most common - values in each column and a histogram showing the approximate data - distribution in each column. One or both of these may be omitted if - ANALYZE deems them uninteresting (for example, in - a unique-key column, there are no common values) or if the column - data type does not support the appropriate operators. There is more - information about the statistics in . + For large tables, ANALYZE takes a random sample + of the table contents, rather than examining every row. This + allows even very large tables to be analyzed in a small amount of + time. Note, however, that the statistics are only approximate, and + will change slightly each time ANALYZE is run, + even if the actual table contents did not change. This may result + in small changes in the planner's estimated costs shown by + EXPLAIN. In rare situations, this + non-determinism will cause the query optimizer to choose a + different query plan between runs of ANALYZE. To + avoid this, raise the amount of statistics collected by + ANALYZE, as described below. The extent of analysis can be controlled by adjusting the - default_statistics_target parameter variable, or on a - column-by-column basis by setting the per-column - statistics target with ALTER TABLE ... ALTER COLUMN ... SET - STATISTICS (see - ). The - target value sets the maximum number of entries in the most-common-value - list and the maximum number of bins in the histogram. The default - target value is 10, but this can be adjusted up or down to trade off - accuracy of planner estimates against the time taken for - ANALYZE and the amount of space occupied - in pg_statistic. - In particular, setting the statistics target to zero disables collection of - statistics for that column. It may be useful to do that for columns that - are never used as part of the WHERE, GROUP BY, or ORDER BY clauses of - queries, since the planner will have no use for statistics on such columns. + DEFAULT_STATISTICS_TARGET parameter variable, or + on a column-by-column basis by setting the per-column statistics + target with ALTER TABLE ... ALTER COLUMN ... SET + STATISTICS (see ). The target value sets the + maximum number of entries in the most-common-value list and the + maximum number of bins in the histogram. The default target value + is 10, but this can be adjusted up or down to trade off accuracy of + planner estimates against the time taken for + ANALYZE and the amount of space occupied in + pg_statistic. In particular, setting the + statistics target to zero disables collection of statistics for + that column. It may be useful to do that for columns that are + never used as part of the WHERE, GROUP BY, + or ORDER BY clauses of queries, since the planner will + have no use for statistics on such columns. diff --git a/doc/src/sgml/ref/create_user.sgml b/doc/src/sgml/ref/create_user.sgml index ff294c63ea..209d67d6ee 100644 --- a/doc/src/sgml/ref/create_user.sgml +++ b/doc/src/sgml/ref/create_user.sgml @@ -1,5 +1,5 @@ @@ -98,7 +98,7 @@ where option can be: These key words control whether the password is stored encrypted in the system catalogs. (If neither is specified, the default behavior is determined by the configuration - parameter password_encryption.) If the + parameter PASSWORD_ENCRYPTION.) If the presented password string is already in MD5-encrypted format, then it is stored encrypted as-is, regardless of whether ENCRYPTED or UNENCRYPTED is specified diff --git a/doc/src/sgml/ref/postmaster.sgml b/doc/src/sgml/ref/postmaster.sgml index 12d879d44f..07c6f2bfc0 100644 --- a/doc/src/sgml/ref/postmaster.sgml +++ b/doc/src/sgml/ref/postmaster.sgml @@ -1,5 +1,5 @@ @@ -376,7 +376,7 @@ PostgreSQL documentation - Default value of the datestyle run-time + Default value of the DATESTYLE run-time parameter. (The use of this environment variable is deprecated.) @@ -563,7 +563,7 @@ PostgreSQL documentation $ postmaster -c sort_mem=1234 $ postmaster --sort-mem=1234 - Either form overrides whatever setting might exist for sort_mem + Either form overrides whatever setting might exist for SORT_MEM in postgresql.conf. Notice that underscores in parameter names can be written as either underscore or dash on the command line. diff --git a/doc/src/sgml/ref/reset.sgml b/doc/src/sgml/ref/reset.sgml index 58169d17de..6f8fc85883 100644 --- a/doc/src/sgml/ref/reset.sgml +++ b/doc/src/sgml/ref/reset.sgml @@ -1,5 +1,5 @@ @@ -85,14 +85,14 @@ SET parameter TO DEFAULT Examples - Set datestyle to its default value: + Set DATESTYLE to its default value: RESET datestyle; - Set geqo to its default value: + Set GEQO to its default value: RESET geqo;