This script is perfect for files with known number of columns
Hi Pamu,
Thanks for your quick reply.
This script is perfectly fine for all files which have equal number of columns.
My challenge is to find 'mode' for files(.csv type) where
1) I don't know how many columns are there unless I open each file and check(very tedious task)
2) Printing the output side by side like mode_of_col1,mode_of_col2 etc.
For the first one i can count the number of columns in each file and feed into variable and loop through.
For the second one I can use the command
to transpose the output.
But all these change are making my code very lengthy and also I need to process many files (some times in 1000's).
Thats why I am looking for automatic looping script to print 'mode' for each column as well as looping to random number of columns.
Can you modify your script if you can ?
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 LINUX
analyze
ANALYZE(7) SQL Commands ANALYZE(7)NAME
ANALYZE - collect statistics about a database
SYNOPSIS
ANALYZE [ VERBOSE ] [ table [ ( column [, ...] ) ] ]
DESCRIPTION
ANALYZE collects statistics about the contents of tables in the database, and stores the results in the pg_statistic system catalog. Subse-
quently, the query planner uses these 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 collected.
PARAMETERS
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
When VERBOSE is specified, ANALYZE emits progress messages to indicate which table is currently being processed. Various statistics about
the tables are printed as well.
NOTES
In the default PostgreSQL configuration, in the documentation takes care of automatic analyzing of tables when they are first loaded with
data, and as they change throughout regular operation. When autovacuum is disabled, 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 VACUUM [vacuum(7)] and ANALYZE once a day during a low-usage
time of day.
ANALYZE requires only a read lock on the target table, so it can run in parallel with other activity on the table.
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 can 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 infor-
mation about the statistics in in the documentation.
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 ANA-
LYZE is run, even if the actual table contents did not change. This might result in small changes in the planner's estimated costs shown by
EXPLAIN [explain(7)]. In rare situations, this non-determinism will cause the planner's choices of query plans to change after ANALYZE is
run. 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 configuration 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 100, 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 might 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
There is no ANALYZE statement in the SQL standard.
SEE ALSO
VACUUM [vacuum(7)], vacuumdb [vacuumdb(1)], in the documentation, in the documentation
SQL - Language Statements 2010-05-14 ANALYZE(7)