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Table is not updating. I used same syntax for updating other tables, but this one is not working

This sql query is not updating the database, instead returning error. Any suggestions?
PreparedStatement ps10 = con.prepareStatement("UPDATE payroll_system.payslip SET hours_worked = (SELECT SUM(Hours) FROM payroll_system.monthly_timesheet WHERE employeeID=?) WHERE employeeID=?");
ps10.setString(1, employee_id);
ps10.setString(2, employee_id);
ps10.executeUpdate();

Try this:
UPDATE payroll_system.payslip as t1
SET hours_worked = (SELECT SUM(Hours) FROM payroll_system.monthly_timesheet WHERE employeeID=t1.employeeID)
WHERE employeeID=?

select scope_identity() using createSQLQuery in Hibernate

I am forced to use createSQLQuery to insert values into tables with an Identity column (the first column and the primary key) using hibernate. Using hibernate classes are not an option since the tables are created on the fly for each customer that is added to the system. I have run the query and it successfully inserts into the table. I then execute a "select scope_identity()" and it always returns null. "select ##Identity" works but that is not guaranteed to be the correct one. I have also tried to append "select scope_identity()" to the insert query. Then I tried query.list() and query.uniqueResult() both of which throw the hibernate exception of "No Results ..."
Session session = DatabaseEngine.getSessionFactory().openSession();
String queryString = "insert into table1 (dataid) values (1)"
SQLQuery query = session.createSQLQuery(insertQueryString);
query.executeUpdate();
query = session.createSQLQuery("select scope_identity()");
BigDecimal entryID = (BigDecimal)query.uniqueResult();
The simple example table is defined as follows:
"CREATE TABLE table1 (EntryID int identity(1,1) NOT NULL," +
"DataID int default 0 NOT NULL, " +
"PRIMARY KEY (EntryID))";
Is there a way I am missing to use scope_identity() with createSQLQuery?

Actually the SQLServerDialect class used by Hibernate uses the same "scope_identity()" too.
The reason why it's not working is because you need to execute those in the same statement or stored procedure.
If you execute the scope_identity() call in a separate statement, SQL Server will not be able to give you last inserted identity value.
You cannot do it with the SQLQuery, even Hibernate uses JDBC to accomplish this task. I wrote a test on GitHub to emulate this and it works like this:
Session session = entityManager.unwrap(Session.class);
final AtomicLong resultHolder = new AtomicLong();
session.doWork(connection -> {
try(PreparedStatement statement = connection.prepareStatement("INSERT INTO post VALUES (?) select scope_identity() ") ) {
statement.setString(1, "abc");
if ( !statement.execute() ) {
while ( !statement.getMoreResults() && statement.getUpdateCount() != -1 ) {
// do nothing until we hit the resultset
}
}
try (ResultSet rs = statement.getResultSet()) {
if(rs.next()) {
resultHolder.set(rs.getLong(1));
}
}
}
});
assertNotNull(resultHolder.get());
The code uses Java 8 lambdas instead of anonymous classes, but you can easily port it to Java 1.7 too.

Using Select and where statement in Criteria

I am in the process of replacing jdbc with hibernate in my Web Application. I have learned that i don't have to write any SQL queries in this. Instead of this,criteria queries can help me.
These are my SQL queries which i want to convert to hibernate using criteria not HQL.
String getOrgIdQuery = "SELECT * FROM USER_DETAILS WHERE USER_ID= ?";
rsDeptName = stmt.executeQuery("SELECT DEPARTMENT_NAME FROM DEPARTMENT WHERE DEPARTMENT_ID ="+ DeptID + ";");
String insertCreateCdcValuesFirst = ("UPDATE User_Details SET User_Name=?, Organization_ID=?, Department_ID=?, Access_Ctrl = ?, User_Role=? WHERE User_ID = ?;");

First off all you must map your table with POJOS.
String getOrgIdQuery = "SELECT * FROM USER_DETAILS WHERE USER_ID= ?";
Preceding code in Hibernate look like following.
Criteria criteria = session.createCriteria(USER_DETAILS.class);
criteria.add(Restrictions.eq("user_id",yourUserId));
List<USER_DETAILS> list = criteria.list();
Your second select query is also same as preceding.
String insertCreateCdcValuesFirst = ("UPDATE User_Details SET User_Name=?, Organization_ID=?, Department_ID=?, Access_Ctrl = ?, User_Role=? WHERE User_ID = ?;");
With Hibernate Criteria update looks like following:
USER_DETAILS user_details = (USER_DETAILES) session.get(USER_DETAILS.class,yourUserId);
user_details.setUser_Name(NewUserName);
user_details.setOrganization_Id(newOrganizationId);
// some other fields update goes here
session.update(user_details);
tx.commit();
I hope this help you.

How to Fetch common column from multiple tables in Database?

Greeting to all smart people around here !!
I have faced a weird interview question regarding SQL.
Qn . If I have 100 tables in Database. I want to fetch common records from Each table.
For example, location is common field in 100 tables. I want to fetch location field from all the tables without mentioning each table name in my SQL query.
Is there any way to do it?
If any possibilities let me know...

get list of tables from db metadata, and then query with each:
Statement stmt = conn.createStatement();
ResultSet locationRs = null;
DatabaseMetaData md = conn.getMetaData();
ResultSet rs = md.getTables(null, null, "%", null);
while (rs.next()) {
locationRs = stmt.executeQuery("SELECT location from "+ rs.getString(3));
System.out.println(locationRs.getString(1));
}

In MSSQL Server you have INFORMATION_SCHEMA.COLUMNS table that contains the column names so you can use group by and having count some value you will get the column name after that you can use pivot to get the values of column names and carry on to it. You will get the ans.
For eg.
Select COLUMN_NAME from INFORMATION_SCHEMA.COLUMNS group BY COLUMN_NAME having count(COLUMN_NAME) > 2
By above query you will get the common column names

You can try this for any Number of Tables in a DB :
select COLUMN_NAME from INFORMATION_SCHEMA.COLUMNS group by COLUMN_NAME having count(COLUMN_NAME)=(select count(*) from INFORMATION_SCHEMA.TABLES)

My friend has found answer for my question..
To get common column from multiple tables,Use INFORMATION_SCHEMA.COLUMNS and common column name.
Query :
select *from information_schema.columns where column_name='column name'
Hope this will helpful !

I am assuming you already have connection and statemnt object's. Now try the below; it might work for you, if not make some adjustments with loops and conditions. Also, you need to have two ResultSet Objects ex: rs1 and rs2. DatabaseMetaData dbmd = con.getMetaData();
String table[] = {"TABLE"} `;
rs1 = dbmd.getTable(null, null, ".*" ,table);
while(rs1.next()){
String tableFrom = rs1.getString(3) ;
rs2 = dbmd.getColumns(null,null,tableFrom , ".*") ;
while(rs2.next()) {
String locColFrom = rs2.getString(3);
if(locColFrom .equalsIgnoreCase("location"))
stmt.executeQuery(select locColFrom from tableFrom ) ;
}
}
Here's an link to study [Oracle] (http://docs.oracle.com/javase/7/docs/api/java/sql/DatabaseMetaData.html#getTables(java.lang.String,%20java.lang.String,%20java.lang.String,%20java.lang.String[]))

problem in setString method.in retrieving data from the table

i have two tables "Table1" with columns user_name,Password and course ID and another table "course" with columns course_id,course_name.I have used the following code to display the course ID from Table1 according to the user_name received from the login page.using ResultSet rs1.now i want to retrieve the course_name from the table "course" according to the course ID receieve from "Table1".for that in the second query pstmt2.setString(1, ); what parameter i should use to get the course_id value from the previous query
HttpSession sess=request.getSession();
String a=(String)sess.getAttribute("user");
String b=(String)sess.getAttribute("pass");
try {
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
Connection con=DriverManager.getConnection("jdbc:odbc:ggg");
Statement st = con.createStatement();
String query="select * from Table1 where user_name=?";
PreparedStatement pstmt=con.prepareStatement(query);
pstmt.setString(1,a);
ResultSet rs1=pstmt.executeQuery();
while(rs1.next())
out.println("<h3>COURSE ID: "+rs1.getString("course ID")+"<h3>");
String query2="SELECT * from course where course_id=?";
PreparedStatement pstmt2=con.prepareStatement(query2);
pstmt2.setString(1,);
ResultSet rs2=pstmt2.executeQuery();
while(rs2.next())
{
out.println("<h3>course name: "+rs2.getString("course_name")+"<h3>");
}

why do you go for two turns of database hit, even though you created one time connection object.
modify the query as below
SELECT * from course where course_id = (select course_id from Table1 where user_name=?);
from this query you noneed to give input of courseid also.

No need to hit database twice to get the results that you need. use the query
Select table1.course_id, course.course_name from table1, course where table1.course_id=course_id and table1.user_name=?

This should set the course_id parameter:
pstmt2.setString(1,rs1.getString("course_id"));
Or, as I see the "course_id" column may have a different name in "Table1":
pstmt2.setString(1,rs1.getString("course ID"));

As the other post mentioned there's no need to go to another set of query. Try this example query:
SELECT course.course_id, course.course_name
FROM table1 t1
INNER JOIN course c
ON t1.course_id = c.course_id
WHERE t1.user_name = ?;
Now if you insist your coding the parameter o your pstmt2.setString(1,); is:
pstmt2.setString(1,rs1.getString("course_id")); //or course ID defending on your column name