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Java and SQLite [closed]
...s test app will create a database file, send some SQL commands to create a table, store some data in the table, and read it back and display on console. It will create the test.db file in the root directory of the project. You can run this example with java -cp .:sqlitejdbc-v056.jar Test.
package ...
Join/Where with LINQ and Lambda
...thods:
var id = 1;
var query = database.Posts // your starting point - table in the "from" statement
.Join(database.Post_Metas, // the source table of the inner join
post => post.ID, // Select the primary key (the first part of the "on" clause in an sql "join" statement)
...
What's the difference between `on` and `live` or `bind`?
...p imbrication (<body><div><div><div><div><table><table><tbody><tr><td><div><div><div><ul><li><button> etc etc etc...)
So, bind, like click, like other shortcut event binders attach directly to the event ...
How many characters can UTF-8 encode?
...
According to this table* UTF-8 should support:
231 = 2,147,483,648 characters
However, RFC 3629 restricted the possible values, so now we're capped at 4 bytes, which gives us
221 = 2,097,152 characters
Note that a good chunk of those chara...
Extract a substring according to a pattern
...sapply(strsplit(string, ":"), "[", 2)
## [1] "E001" "E002" "E003"
3) read.table
read.table(text = string, sep = ":", as.is = TRUE)$V2
## [1] "E001" "E002" "E003"
4) substring
This assumes second portion always starts at 4th character (which is the case in the example in the question):
substring(st...
How can I prevent SQL injection in PHP?
...ng "'Sarah'; DELETE FROM employees", and you will not end up with an empty table.
Another benefit of using prepared statements is that if you execute the same statement many times in the same session it will only be parsed and compiled once, giving you some speed gains.
Oh, and since you asked abo...
How to set a default entity property value with Hibernate
...ld not recommend using columnDefinition for this situation, this is not portable from a database to another, and you need to know the specific SQL language of your server.
– pdem
Sep 20 '16 at 7:30
...
Set a DateTime database field to “Now”
...
In SQL you need to use GETDATE():
UPDATE table SET date = GETDATE();
There is no NOW() function.
To answer your question:
In a large table, since the function is evaluated for each row, you will end up getting different values for the updated field.
So, if yo...
Are database triggers evil? [closed]
...
They are completely Global - they apply no matter what the context of the table activity;
They are stealthy; it's easy to forget they are there until they hurt you with unintended (and very mysterious) consequences.
This just means they need to be carefully used for the proper circumstances; whi...
Replacing NULL with 0 in a SQL server query
...olumn with something else, use IsNull.
SELECT ISNULL(myColumn, 0 ) FROM myTable
This will put a 0 in myColumn if it is null in the first place.
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