Hi Friends,
Can any of you explain me about the below line of code?
mn_code=`env|grep "..mn"|awk -F"=" '{print $2}'`
Im not able to understand, what exactly it is doing :confused:
Any help would be useful for me.
Lokesha (4 Replies)
Hi All,
I have working (Perl) code to combine 2 input files into a single output file using the join function that works to a point, but has the following limitations:
1. I am restrained to 2 input files only.
2. Only the "matched" fields are written out to the "matched" output file and... (1 Reply)
Hi,
I have line in input file as below:
3G_CENTRAL;INDONESIA_(M)_TELKOMSEL;SPECIAL_WORLD_GRP_7_FA_2_TELKOMSEL
My expected output for line in the file must be :
"1-Radon1-cMOC_deg"|"LDIndex"|"3G_CENTRAL|INDONESIA_(M)_TELKOMSEL"|LAST|"SPECIAL_WORLD_GRP_7_FA_2_TELKOMSEL"
Can someone... (7 Replies)
Hello, I was looking for a way to select between the repeated entries (column1) based on the values of absolute values of column 3 (larger value). For example if the same gene id has FC value -2 and 1, I should get the output as -2. Kindly help.
GeneID Description FC ... (2 Replies)
Hi, all, I have a file that looks like:
## XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
## YYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYY
#AA AB AC AD AE AF AG AH AI AJ AK AL
20 60039 60039 ... (5 Replies)
Hi!
I am having 02 files.
In first file" X" I am having 02 Columns
TCP-5100 Sybase_5100
TCP-5600 Sybase_5600
Second file "Y" for example--
:services (
:AdminInfo (
:chkpf_uid ("{A2F79713-B67D-4409-83A4-A90804E983E9}")
:ClassName (rule_services)
)
:compound ()... (12 Replies)
Look at the following data file(cou.data) which has four fields separated by tab.
Four fields are country name, land area, population, continent where it belongs.
As for country name or continent name which has two words, two words are separated by space.
(Data are not accurately... (1 Reply)
Hello.
System : opensuse leap 42.3
I have a bash script that build a text file.
I would like the last command doing :
print_cmd -o page-left=43 -o page-right=22 -o page-top=28 -o page-bottom=43 -o font=LatinModernMono12:regular:9 some_file.txt
where :
print_cmd ::= some printing... (1 Reply)
Discussion started by: jcdole
1 Replies
LEARN ABOUT REDHAT
analyze
ANALYZE(7) SQL Commands ANALYZE(7)NAME
ANALYZE - collect statistics about a database
SYNOPSIS
ANALYZE [ VERBOSE ] [ table [ (column [, ...] ) ] ]
INPUTS
VERBOSE
Enables display of progress messages.
table The name (possibly schema-qualified) of a specific table to analyze. Defaults to all tables in the current database.
column The name of a specific column to analyze. Defaults to all columns.
OUTPUTS
ANALYZE
The command is complete.
DESCRIPTION
ANALYZE collects statistics about the contents of PostgreSQL tables, and stores the results in the system table pg_statistic. Subsequently,
the query planner uses the statistics to help determine the most efficient execution plans for queries.
With no parameter, ANALYZE examines every table in the current database. With a parameter, ANALYZE examines only that table. It is further
possible to give a list of column names, in which case only the statistics for those columns are updated.
NOTES
It is a good idea to run ANALYZE periodically, or just after making major changes in the contents of a table. Accurate statistics will help
the planner to choose the most appropriate query plan, and thereby improve the speed of query processing. A common strategy is to run VAC-
UUM [vacuum(7)] and ANALYZE once a day during a low-usage time of day.
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 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 the User's Guide.
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 ALTER TABLE [alter_table(7)]). 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.
The largest statistics target among the columns being analyzed determines the number of table rows sampled to prepare the statistics.
Increasing the target causes a proportional increase in the time and space needed to do ANALYZE.
COMPATIBILITY
SQL92
There is no ANALYZE statement in SQL92.
SQL - Language Statements 2002-11-22 ANALYZE(7)