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JDBC. Replace in all rows value of the column

Java 11. PostgreSQL.
Having following table in db:
TABLE public.account (
id bigserial NOT NULL,
account_id varchar(100) NOT NULL,
display_name varchar(100) NOT NULL,
is_deleted bool NULL DEFAULT false,
);
There are about 1000 rows in this table. In the code I have a static method, which return random string - Helper.getRandomName()
How, using JDBC, in this table (public.account) for all rows replace "display_name" value with value of Helper.getRandomName()?

This is a SQL question. You need to run an update query:
UPDATE public.account set display_name = ?
And provide the new name as the parameter. The absence of a WHERE clause means that all rows will be affected.
If you want to do this for each row individually, then it's harder. You'll want to do a select statement to find all the IDs, and then you can prepare a batch of updates using JDBC, adding a where clause for each ID.
JDBC is just a thin Java wrapper around plain SQL execution.

SQL syntax error initializing DB before unit Tests

I have created a .sql for preparing my DB for testing.
here a part of the .sql which produces the error:
DROP TABLE IF EXISTS announcement;
CREATE TABLE announcement (
id int(11) NOT NULL AUTO_INCREMENT,
date datetime DEFAULT NULL,
title varchar(255) DEFAULT NULL,
content mediumtext,
PRIMARY KEY (id)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;
LOCK TABLES announcement WRITE;
INSERT INTO announcement VALUES (1,'2015-07-29 10:59:16','Test Anno ','some text');
UNLOCK TABLES;
when executed in Mysql Workbench this scipt works fine.
however when executed via hibernate:
String sqlScript = readFile("dump.sql", Charset.forName("UTF8"));
//System.err.println(sqlScript);
Query q = em.createNativeQuery("BEGIN " + sqlScript + "END;");
q.executeUpdate();
I get:
2015-08-06 16:15:55 ERROR SqlExceptionHelper:146 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'DROP TABLE IF EXISTS announcement;
CREATE TABLE announcement (
id int(11) NO' at line 1
I am using:
Properties jpaProperties = new Properties();
jpaProperties.put("hibernate.dialect","org.hibernate.dialect.MySQL5Dialect");
jpaProperties.put("hibernate.enable_lazy_load_no_trans", true);
Can someone help me out here?
thanks.

As stated by mustaccio BEGIN and END statements are not allowed outside of stored procedueres. See: Hibernate multiple native SQL statements

#1467 - Failed to read auto-increment value from storage engine

I was trying to create a new object and this error appeared:
java.sql.sqlexception failed to read auto-increment value from storage engine
So I went to the phpMyAdmin to create the object there and the same showed up:
MySQL said: Documentation
1467 - Failed to read auto-increment value from storage engine
then I clicked on edit, and it was there:
INSERT INTO `reservation`.`room` (`idroom`, `number`, `floor`, `description`, `characteristics`, `cost`, `status`, `type`) VALUES (NULL, '114', '3', 'ss', 'ss', '550.00', 'Available', 'ss')
(idroom is supposed to be auto-incremented.)
I already read other posts where they say I have to put this:
ALTER TABLE `table_name` AUTO_INCREMENT = 1
but I have no idea where to put that. Is there a better solution?

Your INSERT statement is wrong. Since idroom is AUTO_INCREMENT; you must not include it in the column list on your insert command. Your insert statement should look like below. Notice that I have removed idroom column from insert column list and not passing NULL as well in value list.
INSERT INTO `reservation`.`room` (`number`, `floor`, `description`,
`characteristics`, `cost`, `status`, `type`)
VALUES ('114', '3', 'ss', 'ss', '550.00', 'Available', 'ss')

I also struggled with this problem and searched, and didn't find anything. Then the following worked for me; I guess it might work for your problem. Thx.
1st:
-delete (before backup)->all data from your database.
-try to run your Java program again, or any program you want.
If it fails then go to 2nd.
2nd:
- backup all data from your table
- delete table completely
- create table again; example shown below:
CREATE TABLE `users` (
`id` int(6) NOT NULL,
`f_name` varchar(30) NOT NULL,
`l_name` varchar(30) NOT NULL,
`address` varchar(50) DEFAULT NULL,
`phone_num` varchar(12) DEFAULT NULL,
`email` varchar(30) DEFAULT NULL
);
ALTER TABLE `users`
ADD PRIMARY KEY (`id`);
AUTO_INCREMENT for table `users`
ALTER TABLE `users`
MODIFY `id` int(6) NOT NULL AUTO_INCREMENT;

Assign ID number automatically

strSQL = "INSERT INTO emp(NO, EMP_NAME, EMP_TEL)VALUES(088000, 'JIMMY', *****)";
stmt.executeUpdate(strSQL);
I have this statement to insert a new employee into the database.
What if I want the employee NO to be automatically generated by adding 1 to the previous employee NO? How can this be done in JSP?

While not JSP, a possible solution would be to create an auto generated incrementing column (known as an identity column) in the database. Importantly, this avoids the race condition that exists with a solution that retrieves the current maximum and increments it.
MySQL example:
create table emp (
emp_id integer not null auto_increment,
...
);
Apache Derby example:
create table emp (
emp_id integer not null generated always as identity,
...
);
MS SQL Server 2008 R2 example:
create table emp (
emp_id integer not null identity,
...
);
The INSERT statements do not include the emp_id column. See Statement.getGeneratedKeys() for obtaining generated id if required.

Depending of your DB... I give you a mysql example.
create table emp{
NO int unsigned auto_increment,
EMP_NAME varchar(30) not null,
...
}
insert into emp(EMP_NAME,...) values ("Jimmy", ...);
Now you can ask mysql the last inserted id with
LAST_INSERT_ID()

Yes of course, you can do this by setting "employee no" to be unique and A_I (auto_increament) in this column properties

Check database Schema where you are creating table emp with ID int NOT NULL AUTO_INCREMENT
Then update the schema strSQL = "INSERT INTO emp(EMP_NAME, EMP_TEL) VALUES('ABC_NAME', '321321')";
Though it is possible BUT we should not do any logical operation into JSP. Forward all input in Servlet and do there.

There are several way to do.
Some of databases like Oracle has features like sequence, which allows you to increment numbers sequently and operates as atomic.
Set the column (possibly primary key) to auto increment ( database option ), and do not specify that "NO" in your query. That way, the NO column you didn't add will be added by database automatically.
You can get max values from database table and add 1 for new NO, or you can save those latest value even in file, memcached, whatever you want. The problem of this #3 is, if you don't make program to be atomic between GET LATEST VALUE, ADD 1, CALL DATABASE INSERT QUERY, multiple query can have same NO to use. It's OK, however, if NO is primary key since only very first update/insert query will executed and others query will be failed due to primary key unique violation... but problematic in some cases.

You can use the AUTOINCREMENT option on the field NO on the database, or execute a query like SELECT MAX(NO) FROM emp
and get the max value

I think this will be going to solve your doubt in database and use this following query as:
CREATE TABLE:
CREATE TABLE `test` (
`id` INT(5) UNSIGNED NOT NULL AUTO_INCREMENT,
`emp_name` VARCHAR(50) NOT NULL,
`emp_tel` INT(5) NOT NULL,
PRIMARY KEY (`id`)
) ENGINE=INNODB AUTO_INCREMENT=5 DEFAULT CHARSET=utf8
INSERT TABLE METHOD:1
INSERT INTO test
VALUES (0,jmail,1234567)OR(?,?,?);
INSERT TABLE METHOD:2
INSERT INTO test (id,emp_name,emp_tel)
VALUES (0,jmail,1234567);
If you had any doubt give me comment.
And if your using the sqlyog to use the shortcut.
if your wants this method like following as:
PreparedStatement ps = con.prepareStatement("INSERT INTO test(id,emp_name,emp_tel)
VALUES (0,jmail,1234567)");
ps.executeUpdate();
PreparedStatement ps = con.prepareStatement("INSERT INTO test(id,emp_name,emp_tel)
VALUES (?,?,?)");
ps.setString(1, id );
ps.setString(2, name);
ps.setString(3, tel);
ps.executeUpdate();

Java SQL simple update syntax issue

I have a table named books with bookID, bookName, count , orderCount
i'd like to write an sql query that will update all books.orderCount to books.orderCount+1.
How shall i do that using executeQuery("UPDATE books...."); ?
I'm having troubles with the syntax.
I've tried to search info on the net however most articles are about INSERT or DELETE commands and the only article that was related suggested to retrieve orderCount to Java, update it and then write it back to SQL. if possible i prefer to avoid it as it may cause serious problems (Locks on records are not needed for this task so i can not use them to avoid problems)

this should be pretty straight forward,
UPDATE books
SET orderCount = orderCount + 1

If it's about a primary key:
Also, you can AUTO INCREMENT.
CREATE TABLE Persons
(
P_Id int NOT NULL AUTO_INCREMENT,
LastName varchar(255) NOT NULL,
FirstName varchar(255),
Address varchar(255),
City varchar(255),
PRIMARY KEY (P_Id)
)
To let the AUTO_INCREMENT sequence start with another value, use the following SQL statement:
ALTER TABLE Persons AUTO_INCREMENT=100
To insert a new record into the "Persons" table, we will not have to specify a value for the "P_Id" column (a unique value will be added automatically):
INSERT INTO Persons (FirstName,LastName)
VALUES ('Lars','Monsen')