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For now, just a replacement for ref.pollestad.net.

== PHP Arrays ==
PHP Arrays are easy but it's the multi-arrays that kicked my ass.

Here is how to do a mutli-dimesional array:

Two ways of filling it in:

* $a[1] = array("1", "2", "3");
* $a[2] = array("3", "2", "1");

* $try[] = array("11", "12", "15");
* $try[] = array("6", "7", "16");

Essentially the same thing.

Now, the thing to remember when printing is that the arrays cannot be in quotes.
Example:

* print("$a[0][1]") prints out "Array[1]"

while

* print($a[0][1]) prints out what we want.

Use print("blah" . $a[1][1] . "blah") to include in strings.

== Sed ==
To globally replace every occurance of some pattern within any file:

* cat wrong.txt | sed 's/wrong pattern/good pattern/g' > good.txt
(If you don't use /g, it will only replace the occurrence one per line, but will check every line)

You can also do several substitions on the same file:
* sed -e 's/Second/Third/' -e 's/Third/Fourth/' wrong.txt > good.txt

http://www.suwald.com/linux-gnu/sed-howto.html

== awk ==
Basic awk (prints out a column from a file):
* cat file | awk '{print $2}'

This will print the second column separated by spaces from file.

== Oracle ==
Connecting via command line to SQLPlus:
(be sure that the ORACLE_HOME env variable is set)

* ./sqlplus uid/pwd@TNS:DBNAME

This Oracle SQL statement will display the names of all the tables within the current user's schema:
* SELECT table_name FROM user_tables;

To display the names of all the tables that the current user has access to, use:
* SELECT table_name FROM all_tables;

http://st-curriculum.oracle.com/tutorial/DBXETutorial/index.htm

== SQL ==
- Logical Operators
Listing the names and ages of employees whose last names begin with S or P and who are less than 30 years of age.
* SELECT f_name, l_name , age from employee_data where (l_name like 'S%' OR l_name like 'A%') AND age < 30;

Note the usage of parenthesis in the statement above. The parenthesis are meant to separate the various logical conditions and remove any ambiguity.

http://www.webdevelopersnotes.com/tutorials/sql/sql_primer_logical_operators.php3

- Update (Search/Replace)
When doing an SQL update that requires a search/replace, the following SQL query should do the trick:
* update news set text = replace(text, 'oldtext', 'newtext') where rec=503;

Note that you can also use "trim" fuctions if needed:
* set text = replace(LTRIM(RTRIM(text))

Sample p.net php code would look like this (after performing a fetch_array while() loop...):
* query_db("update news set text = replace(text, '$oldtext', '$newtext') where rec=$rec", 0);

http://www.sqlteam.com/article/using-replace-in-an-update-statement

== tcsh ==
Setting environment variables:
* setenv EDITOR vi

To append:
* setenv PATH $PATH\:/usr/sbin

Be sure to escape any ":" that you add or you'll get an error.

== SSL Certs ==
First, to generate a cert with no password and is self-signed (so Apache doesn't prompt us) (this assumes you have openssl installed and working...):
* ./openssl genrsa -out rpssl.key 1024
* ./openssl req -new -key rpssl.key -out rpssl.csr
* ./openssl x509 -in rpssl.csr -out rpssl.crt -req -signkey rpssl.key -days 3650
(cert is valid for 10 years)
* ./openssl x509 -in rpssl.crt -text -noout
(views the completed cert)

To generate a self-signed with password, simply change the first command to read:
* ./openssl genrsa -des3 -out rpssl.key 1024
(note the -des3 parameter)

The link below also details how to set up your own CA if you want to certify against that.

http://www.vanemery.com/Linux/Apache/apache-SSL.html

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