Java sqlite escape string

Java SQL Escape without using setString

Is there a built-in method to escape a string for SQL? I would use setString, but it happens I am using setString multiple times in the same combined SQL statement and it would be better performance (I think) if the escape happened only once instead of each time I say setString. If I had the escaped string in a variable, I could re-use it. Is there no way to do this in Java? Current method, multi-source search. In reality they are three entirely different where statements including joins, but for this example I will just show the same where for each table.

String q = '%' + request.getParameter("search") + '%'; PreparedStatement s = s("SELECT a,b,c FROM table1 where a = ? UNION select a,b,c from table2 where a = ? UNION select a,b,c FROM table3 where a = ?"); s.setString(1, q); s.setString(2, q); s.setString(3, q); ResultSet r = s.executeQuery(); 

I know this is not a big deal, but I like to make things efficient and also there are situations where it is more readable to use » + quote(s) + » instead of ? and then somewhere down the line you find setString .

@RMT: All characters escaped by setString I do not want the possibility of an injection attack or syntax error due to the value of search.

4 Answers 4

If you use setString for a parameter (e.g. PreparedStatement.setString ), there may well be no actual escaping required — it’s likely that the data will be passed separately from the SQL itself, in a way that doesn’t require escaping.

Do you have any concrete indication that this really is a performance bottleneck? It seems very unlikely that within a database query, the expensive part is setting the parameters locally.

It is unlikely. There is no bottleneck here. I just like to a) efficient code and b) sometimes it is more readable. See last part of my edit.

@George: I disagree about the readability, actually — because using a prepared statement you’re keeping the code separate from the data. But I agree that named parameters are more readable than positional ones 🙂

Short answer: I wouldn’t bother. It’s best to do escaping at the last popssible moment. When you try to escape a string early and keep it around, it becomes much more difficult to verify that all strings have been escaped exactly once. (Escaping a string twice is almost as bad as not escaping it at all!) I’ve seen plenty of programs that try to escape strings early and then run into trouble because they need to update the string and then the programmer forgets to re-do the escape, or they update the escaped version of the string, or they have four strings and they escape three of them, etc. (I was just working on a bug where a programmer did HTML escapes on a string early, then decided he had to truncate the string to fit on a form, and ended up trying to output a string that ended with «&am». That is, he truncated his escape sequence so it was no longer valid.)

The CPU time to escape a string should be trivial. Unless you have a very large number of records or very big strings that are re-used, I doubt the savings would be worth worrying about. You’d probably be better off spending your time optimizing queries: saving a read of one record would probably be worth far more than eliminating 1000 trips through the string escape logic.

Longer answer: There’s no built-in function. You could write one easily enough: Most flavors of SQL just need you to double any single quotes. You may need to also double backslashes or one or two other special characters. The fact that this can be different between SQL engines is one of the big arguments for using PreparedStatements and letting JDBC worry about it. (Personally I think there should be a JDbC function to do escaping that could then know any requirements specific to the DB engine. But there isn’t so that’s how it is.)

In any case, it’s not clear how it would work with a PreparedStatement. There’d have to be some way to tell the PreparedStatement not to escape this string because it’s already been escaped. And who really knows what’s happening under the table in the conversation between JDBC and the DB engine: Maybe it never really escapes it at all, but passes it separately from the query. I suppose there could be an extra parameter on the setString that says «this string was pre-escaped», but that would add complexity and potential errors for very little gain.

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Preventing SQL injection through Java string escape

Refer to this post regarding obtaining a query from a Java SQL PreparedStatement. Additionally, utilizing prepared statements can result in a notable increase in speed, as there is no need to reconstruct queries.

Can this simple String escaping prevent any SQL Injections?

One way to launch an attack is by «loading» it.

Initially, you input the username and bank transfer message into it.

Send a transfer of 0.01 to the recipient with the code 02020.020202.200202. The recipient’s name is ‘johnny tables’; however, be cautious as the name also contains the phrase «drop table foobar —«.

johnny tables\';drop table foobar -- 

Things are going well, as our protection is currently active and our previous attack was unsuccessful. We will now attempt the loading attack.

Our next step is to create a payment order that is scheduled.

It is commonly assumed that a value inserted into a database is safe after being checked once, which is an error.

Send a transaction of 0.01 to the recipient with the address 02020.020202.200202. The recipient’s name is Johnny Tables, and the scheduled transaction will take place one day from now. It is important to note that the recipient’s name contains a potentially harmful SQL injection attempt.

Storing the order in the db

'johnny tables\';drop table foobar--' 

The statement «johnny tables’;drop table foobar—» contains a SQL injection attack, specifically the «drop table» command, which can delete a table in a database.

At the stroke of midnight, the scheduler initiates and commences the scheduled payment iterations.

select name from scheduled where time > x and < y 

so the bank code starts to chrunch

String name = result['name']; String acct = result['acct']; String amt = result['amt']; string query = "insert into payment_process (name,acct,amt) values('"+name+"','"+acct+"','"+amt+"'); 

Suddenly, your table falls with a loud thud. The corresponding code, * , can be applied.

When opting for the manual approach, it is crucial to verify that every variable instance is properly escaped, all Unicode characters are taken into consideration, and all quirks specific to the database engine are accounted for.

Prepared statements offer a substantial speed advantage since rebuilding queries is not necessary. Once created, they can be cached and parameter values can be swapped out easily, making them ideal for iterating through lengthy lists. They are truly a lifesaver in such cases.

The main issue is that he may lack an understanding of prepared statements and how they function. Insecurity can trigger an aggressive and protective behavior, causing one to become fanatical to prevent admitting a lack of knowledge. It's recommended to address this with him directly first, but if he refuses to listen, escalate the matter to his manager. Explain the severity of the issue and the potential risks involved, such as the recent swift hack where a large amount of money was stolen. The responsibility of any hack will ultimately fall on your co-worker and manager.

The functionality of * is subject to the specifics of the query, including joins and unions, and may not be effective in all cases. Please note that the example provided is a simplified version.

How to escape user-supplied parameters with a SQL query?, Use Prepared statement. If you want to escape sql string then check for StringEscapeUtils.escapeSql() . Note that that this method was

Escaping SQL Strings in Java

Using PreparedStatement is both a more secure and easier option.

According to ANSI SQL standards, a single quote must mark the start and end of a string literal. Additionally, the only way to escape a single quote is by using two consecutive single quotes.

To replace a single quote with two single quotes, theoretically, is all that is required. Nevertheless, there are certain issues. For instance, MySQL and other databases may support the backslash as an escape mechanism, which means you may need to double the backslashes as well.

If you're working with MySQL, it's recommended to employ MySQLUtils. However, if you're not using MySQL, you should verify the appropriate escape mechanisms to utilize.

It is possible to utilize a prepared statement, as mentioned in the post "get query from java sql preparedstatement." Another option to consider, as suggested in the same post, is implementing Log4JDBC to manage the situation.

By using either of the options, you can avoid the need to worry about escaping strings to prevent SQL injection. The prepared statement takes care of it for you.

As there is no established approach to manage PHP's mysql_real_escape_string() in Java, I utilized the replaceAll method in a series to address all potential issues and prevent any errors. Below is a snippet of my code:

 state.execute("insert into extractiontext(extractedtext,extractedgroup) values('"+content+"','"+group+"')"); > catch (Exception e)

Java - escape string to prevent SQL injection, One of the easiest ways to prevent an SQL injection in the first place is to use a PreparedStatement , which accepts data to substitute into a

How to correct format a string to prevent against invalid characters in a statement? [duplicate]

Employing prepared statement offers this as a justification.

One advantage of utilizing a PreparedStatement is the availability of various .setXYZ() methods, like .setString(). These methods can automatically handle special characters, such as quotation marks, in the provided SQL statement.

Java - Standard library to escape strings (without prepared statements), Do NOT use Apache Commons StringEscapeUtils.escapeSql() because it does NOT correctly escape sql to prevent sql injections. It has been removed

Standard library to escape strings (without prepared statements)

Because of the security risks associated with SQL injection, it's important to address this significant issue in a more complex way. Rather than resorting to escape sequences, I recommend utilizing SQL ? arguments. This approach is especially effective when searching for specific strings.

SELECT * FROM accounts WHERE name = 'escapedstring1' AND password = 'escapedstring2' 

SELECT * FROM accounts WHERE name = ? AND password = ? 

To utilize your SQL methods, simply provide the injected strings as arguments without any need for escaping. If you are using JDBC, follow these steps. It is unclear whether this approach is applicable to your situation.

String statement = "SELECT * FROM accounts WHERE name = ? AND password = ?"; try < PreparedStatement stmt = databaseConnection.prepareStatement(updateString); // notice that it is 1 based, not 0 (ick) stmt.setString(1, name); stmt.setString(2, password); ResultSet results = stmt.executeQuery(); 

As an illustration, ORMLite, the ORM library I created, exemplifies the process using a select parameter.

Apache Commons is a highly seasoned project that you can utilize.

Prevent SQL injection attacks in a Java program, You need to use PreparedStatement. e.g.. String insert = "INSERT INTO customer(name,address,email) VALUES(?, ?, ?);

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Escape singled quoted string in sqlite java

I am having trouble with a sqlite query where the data contains a single quote. The first is the query from println, followed by the error.

 UPDATE Herb_SCORE_TBL SET Course = 'Orange County Nat'l',Score = '90',Rating = '69.3',Slope = '127',Differential = '17.4' WHERE DateField = '2020-02-08' org.sqlite.SQLiteException: [SQLITE_ERROR] SQL error or missing database (near "l": syntax error) 

This seems like it should be simple enough. When I execute this with DB Browser for sqlite app it works fine. Code for query:

for (int row = 0; row < scoresInCurrentRecord; row++) // Loop thru all scores < String scoreDate = DisplayScores. tableDisplayScores.getModel().getValueAt(row, HandicapMain.DATE_POS).toString(); // Date yyyyMD = convertTableDate(scoreDate); // JTable Date (MM/dd/yy) to row date (yyyy-MM-dd) scoreCourse = DisplayScores. tableDisplayScores.getModel().getValueAt(row, HandicapMain.COURSE_POS).toString(); // Course scoreCourse.replaceAll("'", "\\'"); scoreScore = DisplayScores. tableDisplayScores.getModel().getValueAt(row, HandicapMain.SCORE_POS).toString(); // Score scoreRating = DisplayScores. tableDisplayScores.getModel().getValueAt(row, HandicapMain.RATING_POS).toString(); // Rating scoreSlope = DisplayScores. tableDisplayScores.getModel().getValueAt(row, HandicapMain.SLOPE_POS).toString(); // Slope differential = DisplayScores. tableDisplayScores.getModel().getValueAt(row, HandicapMain.DIFFERENTIAL_POS).toString(); // Differential double dblDifferential = Double.parseDouble(differential); // To double dblDifferential = dblDifferential - reduceBy; // Reduction differential = String.valueOf(dblDifferential); // String String query = " UPDATE " + HandicapMain.scoreTableName + " SET " + "Course = '" + scoreCourse + "'," + "Score = '" + scoreScore + "'," + "Rating = '" + scoreRating + "'," + "Slope = '" + scoreSlope + "'," + "Differential = '" + differential + "'" + " WHERE DateField = '" + yyyyMD + "'"; System.out.println(query); try (PreparedStatement pst = SQLiteConnection.connection. prepareStatement(query)) // Try pst < // pst.execute(); // Execute query >catch (SQLException e) // Catch SQL exception < e.printStackTrace(); >> 

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