Hi,
I am a new learner of join command. Some result really make me confused.
Please kindly help me.
input:
file1:
LEO oracle engineer 210375
P.Jones Office Runner ID897
L.Clip Personl Chief ID982
S.Round UNIX admin ID6
file2:
Dept2C ID897 6 years
Dept5Z ID982 1 year
Dept3S ID6 2... (1 Reply)
example sql:
select a.a1,b.b1,c.c1,d.d1,e.e1
from a
left outer join b on a.x=b.x
left outer join c on b.y=c.y
left outer join d on d.z=a.z
inner join a.t=e.t
I know how single outer or inner join works in sql.
But I don't really understand when there are multiple of them.
can... (0 Replies)
Hello,
My apologies if this has been posted elsewhere, I have had a look at several threads but I am still confused how to use these functions. I have two files, each with 5 columns:
File A: (tab-delimited)
PDB CHAIN Start End Fragment
1avq A 171 176 awyfan
1avq A 172 177 wyfany
1c7k A 2 7... (3 Replies)
I have to join(no other command is allowed) 3 files together. And im aware that i have to sort these files(file1 file2 file3) first before I can join them.
However i have to output these sorted files to some temporary file. i can't just do sort -n file1 > file1 or i get an empty file output. Is... (3 Replies)
Hi,
I have 20 tab delimited text files that have a common column (column 1). The files are named GSM1.txt through GSM20.txt. Each file has 3 columns (2 other columns in addition to the first common column).
I want to write a script to join the files by the first common column so that in the... (5 Replies)
Hi team
Optimizer max permutations and search limit are set to 3.5 million and 10 respectively.The parameter instruct optimizer to evaluate up to 3.5 million permutations for max 10 table joins
I have query with 9 tables joined.
How many combinations will optimizer perform to find best... (1 Reply)
Hello,
This post is already here but want to do this with another way
Merge multiples files with multiples duplicates keys by filling "NULL" the void columns for anothers joinning files
file1.csv:
1|abc
1|def
2|ghi
2|jkl
3|mno
3|pqr
file2.csv:
1|123|jojo
1|NULL|bibi... (2 Replies)
Discussion started by: yjacknewton
2 Replies
LEARN ABOUT BSD
join
JOIN(1) General Commands Manual JOIN(1)NAME
join - relational database operator
SYNOPSIS
join [ options ] file1 file2
DESCRIPTION
Join forms, on the standard output, a join of the two relations specified by the lines of file1 and file2. If file1 is `-', the standard
input is used.
File1 and file2 must be sorted in increasing ASCII collating sequence on the fields on which they are to be joined, normally the first in
each line.
There is one line in the output for each pair of lines in file1 and file2 that have identical join fields. The output line normally con-
sists of the common field, then the rest of the line from file1, then the rest of the line from file2.
Fields are normally separated by blank, tab or newline. In this case, multiple separators count as one, and leading separators are dis-
carded.
These options are recognized:
-an In addition to the normal output, produce a line for each unpairable line in file n, where n is 1 or 2.
-e s Replace empty output fields by string s.
-jn m Join on the mth field of file n. If n is missing, use the mth field in each file.
-o list
Each output line comprises the fields specified in list, each element of which has the form n.m, where n is a file number and m is a
field number.
-tc Use character c as a separator (tab character). Every appearance of c in a line is significant.
SEE ALSO sort(1), comm(1), awk(1)BUGS
With default field separation, the collating sequence is that of sort -b; with -t, the sequence is that of a plain sort.
The conventions of join, sort, comm, uniq, look and awk(1) are wildly incongruous.
7th Edition April 29, 1985 JOIN(1)