How database works?

I found following link: interesting!
http://db.cs.berkeley.edu/papers/fntdb07-architecture.pdf 

Static & dynamic compilation of C code

Static compilation
===================
[root@vilalin05 src]# gcc -m64 -static -o server server.c

confirmation check :
1]execute file command
[root@vilalin05 src]# file server
server: ELF 64-bit LSB executable, AMD x86-64, version 1 (SYSV), for GNU/Linux 2.6.9, statically linked, for GNU/Linux 2.6.9, not stripped
[root@vilalin05 src]#
2]execute ldd command
[root@vilalin05 src]# ldd server
not a dynamic executable
[root@vilalin05 src]#



Dynamic compilation
===================
[root@vilalin05 src]# gcc -m64 -o server server.c

confirmation check:
1]
[root@vilalin05 src]# file server
server: ELF 64-bit LSB executable, AMD x86-64, version 1 (SYSV), for GNU/Linux 2.6.9, dynamically linked (uses shared libs), for GNU/Linux 2.6.9, not stripped

2]
[root@vilalin05 src]# ldd server
libc.so.6 => /lib64/libc.so.6 (0x000000386da00000)
/lib64/ld-linux-x86-64.so.2 (0x000000386d600000)
[root@vilalin05 src]#


||END||

Create a binary file with some data using Perl

Create a binary file with some data using Perl:


#!/usr/bin/perl
open(FH,"> /tmp/binfile") || die "\nUnable to open file for write mode.\n";
for($i = 0;$i<100;$i++){
$bits = pack( "sai", 200, "TEST", 300000 );
print FH $bits;
}


where
s A signed short (16-bit) value. (200)
a A string with arbitrary binary data, will be null padded. (TEST)
i A signed integer value. (300000)

Hashes in shell

Might be one of the way to use “hashes” in ksh

It’s somewhat difficult to use hashes in bash[3* version], however easily possible in korn shell with below code !

#!/bin/ksh

typeset -A newmap

name="mandar"

id="111515"

newmap["name"]=$name

newmap["id"]=$id

echo "${newmap["id"]}"

Might be one of the way to use “array_push” method in ksh:

[root@cllin11 ~]# vim array_push.sh

#!/bin/ksh

typeset -A newmap

map_cnt=0

policy_list=`/usr/openv/netbackup/bin/admincmd/bppllist -l`

for pol in $policy_list

{

    newmap["$map_cnt"]=$pol

    map_cnt=` expr $map_cnt + 1 `

}

i=0

while [ $i -lt $map_cnt ]

do

    echo "${newmap["$i"]}"

    i=` expr $i + 1 `

done