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Postgres query to HQL: select t from TableName t where t.isActive=true order by t.extension->'desc'

Postgres query:
select t
from TableName t
where t.isActive=true
order by t.extcol->'desc'
This work's fine.
Need help with HQL query which will do the same job.
String query = "select t from TableName t where t.isActive=true order by t.extcol->'desc'"
newList = TableNameModel.executeQuery(query);
Method threw 'java.lang.IllegalArgumentException' exception.
context: there is a table TableName where one column is extcol which contains object. Need to sort TableName based on a property desc which present in extcol json object.

For HQL you have the wrong syntax for sorting.
It should be order by t.extcol desc without the arrow and quotes.
see https://docs.jboss.org/hibernate/core/3.3/reference/en/html/queryhql.html#queryhql-ordering

JPA method signature for binary match in mariaDB

In my table of mariaDB database, I have a column name and It is going to store a person's name in any language.
There are 2 names änkür and ankur in table.
If I run below query, it is returning 2 rows
select * from table_name where name ='ankur';
As I want to return single result I changed my query like:
select * from table_name where name = BINARY 'ankur';
What is the JPA method signature or alternative solution for the above query?

How to separate between data selecting from multiple tables?

I want to search in 16 different tables, but I don't wanna repeat the "select from DB" 16 times; I think that's not really help in performance!!!
I am using:
query="SELECT * FROM table1, table2,..., table16 WHERE id=?";
Is it correct ??
my problem is how to separate between data of tables ??
also maybe I can get from one table two or more results for one "id"; So I want to know which data is from which table !!
.
Best regards,

Your query will not work, because you are trying to join those multiple tables, whereas what you want to do is search (filter) those 16 tables.
You could use a union all to do this in a single query:
select xxx, 'table1' as source_table
from table1
where id = ?
union all
select xxx, 'table2' as source_table
from table2
where id = ?
and so on. The second derived field source_table can be used to determine which table returned which result.

You have to list all fields using aliases for fields with same name, and prefix with table names.
For example :
query = "SELECT table1.id as id_1, table2.id as id_2, ... WHERE id_1 = 23"
Probably a very long query to write, but you have solution to generate and paste it : You can do this for example with FlySpeed SqlQuery (free for personal use)
FlySpeed SqlQuery will generate all aliases for you, and automatically prefix with table names.

A little clarification would help. If all 16 tables have the same fields and you want them in a continuous list, you can use UNION as suggested above. On the other hand, if there are only a few fields that match and you want to compare the values for each table side-by-side, you'll want to use joins and provide aliases with the table names, as also suggested above.
However, looking at the snippet of code you've provided, I'm going to guess that you're either building some kind of stored procedure or else implementing SQL in some other language. If that's the case, how about loading your table names into an array and using a for loop to build the query, such as the following psuedo-code:
tableList = ["table1", "table2"...]
fieldnames = ["field1", "field2"...]
query = "SELECT "
for i = 0 to count(tableList):
for j = 0 to count(fieldnames):
query = query + tablelist[i] + "." + fieldnames[j] + ", "
j++
i++
query = query + "FROM "
for i = 0 to count(tableList):
query = query + tableList[i] + ", "
i++
query = query + "WHERE " ...
And so forth. Much of this depends on what exactly you're looking to do, how often you're looking to do it, and how often the variables (like which tables or fields you're using) are going to change.

SQL Update : WHERE clause error

I don't know whats wrong with this query :
SQL = "UPDATE "+ choosenClass +" SET COUNT = "+count+" WHERE NAME = "+names;
stmt2.executeUpdate( SQL );
Error :
java.sql.SQLSyntaxErrorException: Column 'RAMAYAH' is either not in any table in the FROM list or appears within a join specification and is outside the scope of the join specification or appears in a HAVING clause and is not in the GROUP BY list. If this is a CREATE or ALTER TABLE statement then 'RAMAYAH' is not a column in the target table.
It says Column RAMAYAH is not there but the string "RAMAYAH" itself is taken from the same table. Help Please.

Try to enclose the string into single quotes:
SQL = "UPDATE "+ choosenClass +" SET COUNT = "+count+" WHERE NAME = '"+names+"'";
stmt2.executeUpdate( SQL );

Apart from SQL-Injection vulnerability as mentioned by others in comment; your query has few more mistakes/issues.
You need to quote the filter value in WHERE condition WHERE NAME = "+names should be
WHERE NAME = '"+names+"'". Otherwise, your query will be formed like below and query engine will presume that there exist a column named RAMAYAH in your table in question.
UPDATE tab1 SET COUNT = 10 WHERE NAME = RAMAYAH;
Also, in your UPDATE statement, you have a column names COUNT which is a reserve word. You need to escape it to be in safe side.
If you are using mysql then use backtique
for sql-server use [] square bracket
for postgresql and oracle use "" double-quote

Run Oracle query from Java

I want to run the query: "DESCRIBE table_name;"
statement = this.connection.createStatement();
ResultSet rset = statement.executeQuery("DESCRIBE table_name");
and I got this error:
" java.sql.SQLSyntaxErrorException: ORA-00900: invalid SQL statement"
what is the problem?

DESC[RIBE] is a SQL*Plus command, not a SQL statement. The DESC command queries the Oracle data dictionary, something like:
select COLUMN_NAME, DATA_TYPE
from USER_TAB_COLUMNS
where TABLE_NAME = 'YOUR_TABLE'

DESC is a SQL*Plus command. SO, you cannot use it via JDBC/ODBC.
An alternative can be like this below.
select RPAD(COLUMN_NAME,30)||' '||DATA_TYPE||'('||DATA_LENGTH||')' as descr
FROM all_tab_cols
WHERE TABLE_NAME = UPPER('YOUR_TABLE') and owner=UPPER('SCHEMA_NAME');
all_tab_cols is a data dictionary table(view) which contains the table metadata
Oracle's Reference

describe user2.flights;
Here user2 is database name and flights is table name. Try this.
Or use next query
select *
from user_tab_columns
where table_name = 'MY_TABLE'
order by column_id;
Use this query.
column_id is the "order" of the column in the table.
You should ensure that 'MY_TABLE' is capitalised unless you've been adding tables with casing ( a bad idea ) in which case you need to use something like = "MyTable"