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Retrieve generated keys from multiple queries in single Spring JDBC Update

I am using a single Spring JDBC update to make an update to two tables in my Postgres database. My SQL query is as follows:
UPDATE accounts SET last_transaction_amount = :transaction_amount WHERE acct_num = :acct_num; INSERT INTO transactions (transaction_amout) VALUES (:transaction_amount);
Using NamedParameterJdbcTemplate#update, I have no issue executing this query and achieving the expected results.
The transactions table generates a sequential transaction identifier, and I want to return this to my application.
I've tried passing a GeneratedKeyHolder in the update call. This is returning the error "A result was returned when none was expected". Docs link.
I've tried passing a GeneratedKeyHolder and array of column names (new String[] {"transaction_id"}). This is returning the error that the column doesn't exist. Note this method call does work to return the transaction id when I only pass the INSERT query without the preceding UPDATE query. Docs link.
How can I retrieve the generated key? Thank you!

You seem to be looking for the RETURNING clause. Assuming that the serial number is called transaction_id:
INSERT INTO transactions (transaction_amout)
VALUES (:transaction_amount)
RETURNING transaction_id;

java8 + mariadb 5.6: How to get autogenerated value when insert a blob

I have a mariadb table with 2 cols: rowid int pk autogenerated and imagen blob.
By using "CallableStatement sentence = mariaConn.prepareCall(myinsert);" I'm able to add a new row with a blob into "imagen" BUT I can't get the autogenerated pk col "rowid".
By the other hand, using "Statement sentence = mariaConn.prepareStatement(myinsert);" I can get the autogenerated col "rowid" but I can't add a blob into "imagen" (only do if it is empty).
Is there a way to do both things at one call? (trying to avoid a Statement insert to get the pk and then a CallableStatement to update the blob).
Note: in Oracle is pretty simple using CallableStatement because Oracle's insert has a "returning" clause <= I'm trying to emulate it on mariadb.
Thanks in advance.

you do not need CallableStatement to insert blob, a simple prepared statement
insert into table(imagen) values(?)
works,and with that you can get autogenerated value if you use Statement.RETURN_GENERATED_KEYS during preparation, and Statement.getGeneratedKeys() after execution. You also can do
select last_insert_id()
any time, but this is less efficient.
There is no MariaDB 5.6 btw.

How can I get an id for a new record in a generic way? (JOOQ 3.4 with Postgres)

With jooq 3.4 I can't figure out how to do this (with Postgresql):
Query query = dsl.insertInto(TABLE)
.set(TABLE.ID, Sequences.TABLE_ID_SEQ.nextval());
but in a case when I don't know which is the exact table, something like this:
TableImpl<?> tableImpl;
Query query = dsl.insertInto(tableImpl)
.set(tableImpl.getIdentity(), tableImpl.getIdentity().getSequence().nextval());
Is it somehow possible?
I tried this:
dsl.insertInto(tableImpl)
.set(DSL.field("id"),
tableImpl.getSchema().getSequence("table_id_seq").nextval())
This works but I still don't know how to get the sequence name from the TableImpl object.
Is there a solution for this? Or is there a problem with my approach?
In plain SQL I would do this:
insert into table_A (id) VALUES nextval('table_A_id_seq');
insert into table_B (table_A_id, some_val) VALUES (currval('table_A_id_seq'), some_val);
So I need the value or a reference to that id for later use of the id that was generated for the inserted record as default, but I don't want to set any other values.

jOOQ currently doesn't have any means of associating a table with its implicitly used sequence for the identity column. The reason for this is that the sequence is generated when the table is created, but it isn't formally connected to that table.
Usually, you don't have to explicitly set the serial value of a column in a PostgreSQL database. It is generated automatically on insert. In terms of DDL, this means:
CREATE TABLE tablename (
colname SERIAL
);
is equivalent to specifying:
CREATE SEQUENCE tablename_colname_seq;
CREATE TABLE tablename (
colname integer NOT NULL DEFAULT nextval('tablename_colname_seq')
);
ALTER SEQUENCE tablename_colname_seq OWNED BY tablename.colname;
The above is taken from:
http://www.postgresql.org/docs/9.3/static/datatype-numeric.html#DATATYPE-SERIAL
In other words, just leave out the ID values from the INSERT statements.
"Empty" INSERT statements
Note that if you want to create an "empty" INSERT statement, i.e. a statement where you pass no values at all, generating a new column with a generated ID, you can use the DEFAULT VALUES clause.
With SQL
INSERT INTO tablename DEFAULT VALUES
With jOOQ
DSL.using(configuration)
.insertInto(TABLENAME)
.defaultValues()
.execute();
Returning IDs
Note that PostgreSQL has native support for an INSERT .. RETURNING clause, which is also supported by jOOQ:
With SQL
INSERT INTO tablename (...) VALUES (...) RETURNING ID
With jOOQ
DSL.using(configuration)
.insertInto(TABLENAME, ...)
.values(...)
.returning(TABLENAME.ID)
.fetchOne();

Atomically fetch and increase sequence value in MySql

I convert the DB from Oracle to MySQL.
I'm using both Java & Hibernate.
When I used oracle I had the following method that gave me a brand new and unused sequence value:
protected int getSequenceNextValue() {
Session session = sessionFactory.getCurrentSession();
Query query = session.createSQLQuery("select MY_SEQUENCE.NEXTVAL from DUAL");
return ((BigDecimal) query.uniqueResult()).intValueExact();
}
And I'm trying to refactor this method to work on MySQL DB.
I have a table in MySQL that I use as a sequence (through Hibernate):
create table MY_SEQUENCE(
next_val int(10) NOT NULL
);
Is there any thread safe way to get a new value from this table and in the same transction to increase it?
For most cases I use the Hibernate Generator to generate a new sequence using this table, but in several cases I need to do it manually.
The best solution for me will be a refactoring of the method above, in such way that threads that querying the table at the same time will not fail, but will wait for each other.
Thanks...

Have a look at the InnoDB table type and FOR UPDATE. An example similar to what you describe is in the MySQL manual here http://dev.mysql.com/doc/refman/5.0/en/innodb-locking-reads.html

How to invertly select columns in sql?

If I have a SQL table with columns:
NR_A, NR_B, NR_C, NR_D, R_A, R_B, R_C
and on runtime, I add columns following the column's sequence such that the next column above would be R_D followed by R_E.
My problem is I need to reset the values of columns that starts with R_ (labeled that way to indicate that it is resettable) back to 0 each time I re-run my script . NR_ columns btw are fixed, so it is simpler to just say something like:
UPDATE table set col = 0 where column name starts with 'NR_'
I know that is not a valid SQL but I think its the best way to state my problem.
Any thoughts?
EDIT: btw, I use postgres (if that would help) and java.

SQL doesn't support dynamically named columns or tables--your options are:
statically define column references
use dynamic SQL to generate & execute the query/queries
Java PreparedStatements do not insulate you from this--they have the same issue, just in Java.

Are you sure you have to add columns during normal operations? Dynamic datamodels are most of the time a realy bad idea. You will see locking and performance problems.
If you need a dynamic datamodel, take a look at key-value storage. PostgreSQL also has the extension hstore, check the contrib.

If you don't have many columns and you don't expect the schema to change, just list them explicitly.
UPDATE table SET NR_A=0;
UPDATE table SET NR_B=0;
UPDATE table SET NR_C=0;
UPDATE table SET NR_D=0;
Otherwise, a simple php script could dynamically build and execute your query:
<?php
$db = pg_connect("host=localhost port=5432 user=postgres password=mypass dbname=mydb");
if(!$db) die("Failed to connect");
$reset_cols = ["A","B","C","D"];
foreach ($col in $reset_cols) {
$sql = "UPDATE my_table SET NR_" . $col . "=0";
pg_query($db,$sql);
}
?>
You could also lookup table's columns in Postgresql by querying the information schema columns tables, but you'll likely need to write a plpgsql function to loop over the query results (one row per table column starting with "NR_").

if you rather using sql query script, you should try to get the all column based on given tablename.
maybe you could try this query to get all column based on given tablename to use in your query.
SELECT attname FROM
pg_attribute, pg_type
WHERE typname = 'tablename' --your table name
AND attrelid = typrelid
AND attname NOT IN ('cmin', 'cmax', 'ctid', 'oid', 'tableoid', 'xmin', 'xmax')
--note that this attname is sys column
the query would return all column with given tablename except system column