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How to add column if not exists on PostgreSQL?
...t pass these as parameters, you'll need to do variable substitution in the string on the client side, but this is a self contained query that only emits a message if the column already exists, adds if it doesn't and will continue to fail on other errors (like an invalid data type).
I don't recommend...
How to use OpenSSL to encrypt/decrypt files?
...bove!
-K key
The actual key to use: this must be represented as a string
comprised only of hex digits. If only the key is specified, the
IV must additionally be specified using the -iv option. When
both a key and a password are specified, the key given with the
-K option wi...
Is it safe to use Project Lombok? [closed]
...le range for a numeric value? Or the permissible length and/or format of a String value? Or whether a String value is suitable for presenting to an end user? Or documenting what the property actually means, when its name can't possibly explain it in full? (JList.getLayoutOrientation and JList.setLay...
Set value to NULL in MySQL
...d'] == '')) {
$val = 'NULL';
} else {
$val = "'" . mysql_real_escape_string($_POST['nullfield']) . "'";
}
$sql = "INSERT INTO .... VALUES ($val)";
if you put 'NULL' into your query, then you're just inserting a 4-character string. Without the quotes, NULL is the actual null value.
...
Determine if Android app is being used for the first time
...is over.
This is my code to catch the first time you open the app:
final String PREFS_NAME = "MyPrefsFile";
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
if (settings.getBoolean("my_first_time", true)) {
//the app is being launched for first time, do something
...
What exactly does += do in python?
... # empty list
x += "something" # iterates over the string and appends to list
print(x) # ['s', 'o', 'm', 'e', 't', 'h', 'i', 'n', 'g']
versus
x=[] # empty list
x = x + "something" # TypeError: can only concatenate list (not "str") to list...
How can I use swift in Terminal?
...
5> println(myVariable)
50
6> let label = "The width is "
label: String = "The width is "
7> let width = 94
width: Int = 94
8> let widthLabel = label + String(width)
widthLabel: String = "The width is 94"
9> :exit
GoldCoast:~ macmark$
...
“Too many values to unpack” Exception
...no Borini, I am getting also similar error but in my case, I am creating a string as obj='{"vendorId": "' + vID +'", "vendorName" :"'+vName+'", "addedDate" : "'+vAddedDate+'","usersList" : "'+ usersList + '," status" : "'+str(vStatus)+'","edit"'+edit+'"}'; although all the values are string, it give...
How to format a java.sql Timestamp for displaying?
How do I formate a java.sql Timestamp to my liking ? ( to a string, for display purposes)
7 Answers
...
How does this checkbox recaptcha work and how can I use it?
... verify the "g-recaptcha-response" control is filled in:
protected static string ReCaptcha_Key, ReCaptcha_Secret;
protected void btnSubmit_Click(object sender, EventArgs e)
{
if (!String.IsNullOrEmpty(Request.Form["g-recaptcha-response"]))
{
// other code
} else
{
lb...