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Hello to everyone.

I am new in the forum, and my first post is going to be about mySQL. I am a total novice in mySQL and the problem i have is that i want to put a specific filter in reading some data.
I have created a database with one table, which has 4 columns, let's say C1, C2, C3, C4.
I have created the interface in java, through which the data is inserted in the dbase.

String insertStr =
				"INSERT INTO `"+dbName+"`.`"+tableName+"` VALUES (CURRENT_TIMESTAMP , '"+
					m.get_C1() + "', '" +	
					m.get_C2()+"', '"+
					m.get_C3()+"', '"+
					m.get_C4()+"');";

			stmt.executeUpdate(insertStr);

Now, i want to start reading the data, in a specific way:
I want to read the C1,2,3,4 data of the line in which has C1=1 and the C2 is the maximum. Actually, i want to know C3,4 of this line through this filter.
the SELECT i am going to make is of that type:

String selectStr=
SELECT data1, data2, data3 FROM 'dbName'

The problem is how i am going to put a filter in this.
Also, is there a spexific code through which i can assign the data in java to some values?

Sorry if my long post was tiring, i hope somebody can give some help.
Thanks in advance,

Xaris

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Last Post by javmedia
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Dont filter in the external application as it is faster to issue constraints in your calling query in this case.

using PHP style for readability

"SELECT `c3`,`c4`
 FROM `MyTable`
 WHERE `c1`='$c1Value' AND `c2`='$c2Value'
 LIMIT $maxDisplayedResultsCount;"

or for range

"SELECT `c3`,`c4`
 FROM `MyTable`
 WHERE (`c1`>='$c1ValueMin' AND `c1`<'$c1ValueMax') AND `c2`='$c2Value'
 LIMIT $maxDisplayedResultsCount;"

On the JAVA part you lost me... :)


Or did you mean filter before INSERT or filter on new SELECT statement?

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