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Multiple queries executed in java in single statement
... it is possible to execute something like this using JDBC.
"SELECT FROM * TABLE;INSERT INTO TABLE;"
Yes it is possible. There are two ways, as far as I know. They are
By setting database connection property to allow multiple queries,
separated by a semi-colon by default.
By calling a stored pro...
NOT IN vs NOT EXISTS
...OT IN sub query were to return no results at all (i.e. the [Order Details] table is empty). In which case it should. In the plan for my sample data this is implemented by adding another anti semi join as below.
The effect of this is shown in the blog post already linked by Buckley. In the example...
Algorithm to find top 10 search terms
...ue ID for each. This whole set of data can be loaded into memory as a hash table, consuming roughly 300MB memory. (We have implemented our own hash table. The Java's implementation takes huge memory overhead)
Each phrase then can be identified as an array of integers.
This is important, because s...
How to implement a rule engine?
I have a db table that stores the following:
10 Answers
10
...
Number of rows affected by an UPDATE in PL/SQL
...s with the number of line affected by the last DML operation:
say we have table CLIENT
create table client (
val_cli integer
,status varchar2(10)
)
/
We would test it this way:
begin
dbms_output.put_line('Value when entering the block:'||sql%rowcount);
insert into client
se...
Are PDO prepared statements sufficient to prevent SQL injection?
...ght get to see someone else's password. Since the first few names in users table tend to be admins, you may have also just given away the farm. (Also note: this is one more reason not to store passwords in plain text!)
We see, then, that prepared statements are enough for a single query, but by the...
Efficiently updating database using SQLAlchemy ORM
...ows one by one.
Instead you should do this:
session.execute(update(stuff_table, values={stuff_table.c.foo: stuff_table.c.foo + 1}))
session.commit()
This will execute as one query as you would expect, and because at least the default session configuration expires all data in the session on commi...
Remove data.frame row names when using xtable
...and I assume it's quite easy too. I'm writing a report and I want to use xtable package for LaTeX table generation (note that memisc package does the job, but say I want to do this solely with xtable ).
...
Cleanest way to build an SQL string in Java
...pared statements:
PreparedStatement stm = c.prepareStatement("UPDATE user_table SET name=? WHERE id=?");
stm.setString(1, "the name");
stm.setInt(2, 345);
stm.executeUpdate();
The other thing that can be done is to keep all queries in properties file. For example
in a queries.properties file can ...
What are .dex files in Android?
...lication code file.
Android programs are compiled into .dex (Dalvik Executable) files, which are in turn zipped into a single .apk file on the device. .dex files can be created by automatically translating compiled applications written in the Java programming language.
Dex file format:
1. File ...