This is something that I've been scratching my head with - especially since it's infuriating to deal with.
Consider the following code:
String query = "UPDATE ORDERS SET VOLUME=?,CONTRACT_ID=?,PROJECT_ID=?,WORKSITE_ID=?,DROPZONE_ID=?,DESCRIPTION_ID=?,MANAGER_ID=?,DELIVERY_DATE=?,REVISION=REVISION+1) WHERE ID=?";
jdbcTemplate.update(query, orderEntity.getVolume(), orderEntity.getContractNo(), orderEntity.getProjectID(), orderEntity.getWorksiteID(), orderEntity.getDropzoneID(), orderEntity.getDescriptionID(), orderEntity.getManagerID(), orderEntity.getDeliveryDate(), id);
We can see that the SQL query is incorrect - and will therefore throw some SQL error but one might have missed that. Spring will (for me) throw a QueryTimeoutException in response to this. I'm sort of okay with that but it's not helpful.
Now let's try
String query = "INSERT INTO ORDERS(ID,REISION,CONTRACT_ID,PROJECT_ID,WORKSITE_ID,DROPZONE_ID,DESCRIPTION_ID,MANAGER_ID,VOLUME,DELIVERY_DATE) VALUES(?,?,?,?,?,?,?,?,?,?)";
jdbcTemplate.update(query, id, revision, etc);
Another spelling mistake that's easily missed - REVISION is misspelled as REISION) Spring throws another QueryTimeoutException again. This now means that if I get that exception I don't actually know what it is. Is it a syntax error? Is it a column spelling error? Is it the (much harder to notice) fact that the foreign key constraint not being followed?
While debugging, this is quite possibly the most infuriating thing ever - all I know is that my query failed to run. How can I get something useful? Is there something I've not added to my pom.xml file?
EDIT:
Here's a nicer example. I have a DESCRIPTIONS table, with an ID, REVISION and TEXT column. All of those are marked as not being nullable.
DescriptionEntity descriptionEntity = new DescriptionEntity("newDesc", 1, null);
String query = "INSERT INTO DESCRIPTIONS (ID,REVISION,TEXT) VALUES(?,?,?)";
jdbcTemplate.update(query, descriptionEntity.getID(), 1, descriptionEntity.getText());
That will also throw a query timeout exception, when running the query in mysql gives me ERROR 1048 (23000): Column 'TEXT' cannot be null
This is, to put it politely, a bit of a pain.
It's not a spelling mistake in the first example, as you left out the opening paren. I would say this isn't an issue with Spring or JDBC, but rather your DB is trying to process the SQL, waiting for more input or something, and never returning.
In the second one, I am not sure what you are talking about since I don't know the table design. I have to assume what you mean is ID is not unique? Again, I wouldn't blame Spring or JDBC, maybe the drive, most likely the database server.
Keep in mind, in a lot of cases, the way SQL is handled in the user Client UI is not the same as how it gets handled through JDBC. For instance, in SQL Server the SQL is set as a string, the passed in parameters set as variables, and it uses sp_executesql() to run it. I discovered that when I had a report that ran PERFECTLY fine through SQL Studio Manager client, but blew up when I ran it live because the query plan optimizer took a different path due to the differences in how the SQL was ran.
This is quite possibly the most stupid error I've ever come across: the issue was in how Maven resolved all the dependencies.
The requirement for Spring Security was placed before the JDBC requirement. That made Spring Security pull down org.springframework:spring-tx:jar:3.0.7.RELEASE:compile which satisfied the dependency for JDBC. Moving the JDBC requirement up meant JDBC pulled down org.springframework:spring-tx:jar:3.2.2.RELEASE:compile.
Related
I am getting below exception, when trying to insert a batch of rows to an existing table
ORA-00942: table or view does not exist
I can confirm that the table exists in db and I can insert data to that table using oracle
sql developer. But when I try to insert rows using preparedstatement in java, its throwing table does not exist error.
Please find the stack trace of error below
java.sql.SQLException: ORA-00942: table or view does not exist
at oracle.jdbc.dbaccess.DBError.throwSqlException(DBError.java:134)
at oracle.jdbc.ttc7.TTIoer.processError(TTIoer.java:289)
at oracle.jdbc.ttc7.Oall7.receive(Oall7.java:573)
at oracle.jdbc.ttc7.TTC7Protocol.doOall7(TTC7Protocol.java:1889)
at oracle.jdbc.ttc7.TTC7Protocol.parseExecuteFetch(TTC7Protocol.java:1093)
at oracle.jdbc.driver.OracleStatement.executeNonQuery(OracleStatement.java:2047)
at oracle.jdbc.driver.OracleStatement.doExecuteOther(OracleStatement.java:1940)
at oracle.jdbc.driver.OracleStatement.doExecuteWithTimeout>>(OracleStatement.java:2709)
at oracle.jdbc.driver.OraclePreparedStatement.executeUpdate(OraclePreparedStatement.java:589)
at quotecopy.DbConnection.insertIntoDestinationDb(DbConnection.java:591)
at quotecopy.QuoteCopier.main(QuoteCopier.java:72)
Can anyone suggest the reasons for this error ?
Update : Issue solved
There was no problem with my database connection properties or with my table or view name. The solution to the problem was very strange. One of the columns that I was trying insert was of Clob type. As I had a lot of trouble handling clob data in oracle db before, gave a try by replacing the clob setter with a temporary string setter and the same code executed with out any problems and all the rows were correctly inserted!!!.
ie. peparedstatement.setClob(columnIndex, clob)
was replaced with
peparedstatement.setString(columnIndex, "String")
Why an error table or view does exist error was throws for error in inserting clob data. Could anyone of you please explain ?
Thanks a lot for your answers and comments.
Oracle will also report this error if the table exists, but you don't have any privileges on it. So if you are sure that the table is there, check the grants.
There seems to be some issue with setCLOB() that causes an ORA-00942 under some circumstances when the target table does exist and is correctly privileged. I'm having this exact issue now, I can make the ORA-00942 go away by simply not binding the CLOB into the same table.
I've tried setClob() with a java.sql.Clob and setCLOB() with an oracle.jdbc.CLOB but with the same result.
As you say, if you bind as a string the problem goes away - but this then limits your data size to 4k.
From testing it seems to be triggered when a transaction is open on the session prior to binding the CLOB. I'll feed back when I've solved this...checking Oracle support.
There was no problem with my database connection properties or with my table or view name. The solution to the problem was very strange. One of the columns that I was trying insert was of Clob type. As I had a lot of trouble handling clob data in oracle db before, gave a try by replacing the clob setter with a temporary string setter and the same code executed with out any problems and all the rows were correctly inserted!!!.
ie. peparedstatement.setClob(columnIndex, clob)
was replaced with
peparedstatement.setString(columnIndex, "String")
#unbeli is right. Not having appropriate grants on a table will result in this error. For what it's worth, I recently experienced this. I was experiencing the exact problem that you described, I could execute insert statements through sql developer but would fail when using hibernate. I finally realized that my code was doing more than the obvious insert. Inserting into other tables that did not have appropriate grants. Adjusting grant privileges solved this for me.
Note: Don't have reputation to comment, otherwise this may have been a comment.
We experienced this issue on a BLOB column. Just in case anyone else lands on this question when encountering this error, here is how we resolved the issue:
We started out with this:
preparedStatement.setBlob(parameterIndex, resultSet.getBlob(columnName)); break;
We resolved the issue by changing that line to this:
java.sql.Blob blob = resultSet.getBlob(columnName);
if (blob != null) {
java.io.InputStream blobData = blob.getBinaryStream();
preparedStatement.setBinaryStream(parameterIndex, blobData);
} else {
preparedStatement.setBinaryStream(parameterIndex, null);
}
I found how to solve this problem without using JDBC's setString() method which limits the data to 4K.
What you need to do is to use preparedStatement.setClob(int parameterIndex, Reader reader). At least this is what that worked for me. Thought Oracle drivers converts data to character stream to insert, seems like not. Or something specific causing an error.
Using a characterStream seems to work for me. I am reading tables from one db and writing to another one using jdbc. And i was getting table not found error just like it is mentioned above. So this is how i solved the problem:
case Types.CLOB: //Using a switch statement for all columns, this is for CLOB columns
Clob clobData = resultSet.getClob(columnIndex); // The source db
if (clobData != null) {
preparedStatement.setClob(columnIndex, clobData.getCharacterStream());
} else {
preparedStatement.setClob(columnIndex, clobData);
}
clobData = null;
return;
All good now.
Is your script providing the schema name, or do you rely on the user logged into the database to select the default schema?
It might be that you do not name the schema and that you perform your batch with a system user instead of the schema user resulting in the wrong execution context for a script that would work fine if executed by the user that has the target schema set as default schema. Your best action would be to include the schema name in the insert statements:
INSERT INTO myschema.mytable (mycolums) VALUES ('myvalue')
update: Do you try to bind the table name as bound value in your prepared statement? That won't work.
It works for me:
Clob clob1;
while (rs.next()) {
rs.setString(1, rs.getString("FIELD_1"));
clob1 = rs.getClob("CLOB1");
if (clob1 != null) {
sta.setClob(2, clob1.getCharacterStream());
} else {
sta.setClob(2, clob1);
}
clob1 = null;
sta.setString(3, rs.getString("FIELD_3"));
}
Is it possible that you are doing INSERT for VARCHAR but doing an INSERT then an UPDATE for CLOB?
If so, you'll need to grant UPDATE permissions to the table in addition to INSERT.
See https://stackoverflow.com/a/64352414/1089967
Here I got the solution for the question. The problem is on glass fish if you are using it. When you create JNDI name make sure pool name is correct and pool name is the name of connection pool name that you are created.
On our production application we recently become weird error from DB2:
Caused by: com.ibm.websphere.ce.cm.StaleConnectionException: [jcc][t4][2055][11259][4.13.80] The database manager is not able to accept new requests, has terminated all requests in progress, or has terminated your particular request due to an error or a force interrupt. ERRORCODE=-4499, SQLSTATE=58009
This occurs when hibernate tries to select data from one big table(More than 6 milions records and 320 columns).
I observed that when ResultSet lower that 10 elements, hibernate selects successfully.
Our architecture:
Spring 4.0.3
Hibernate 4.3.5
DB2 v10 z/Os
Websphere 7.0.0.31(with JDBC V9.7FP5)
This select works when I tried to executed this in Data Studio or when app is started localy from Tomcat(connected to production Data Source). I suppose that Data Source on Websphere is not corectly configured, but I tried some modifications and without results. I also tried to update JDBC Driver but that not helped. Actually I become then ERRORCODE = -1244.
Ok, so now I'm looking for any help ;).
I can obviously provide additional information when needed.
Maybe someone fighted earlier with this problem?
Thanks in advance!
We have the same problem and finally solved by running REORG and RUNSTAT on the table(s). In our case, databse and tables were damaged and after running both mentioned operations, it resolved.
This occurs when hibernate tries to select data from one big table(More than 6 milions records and 320 columns)
6 million records with 320 columns seems huge to be read at once through hibernate. How you tried creating a database cursor and streaming few records at a time? In plain JDBC it is done as follows
Statement stmt = conn.createStatement(java.sql.ResultSet.TYPE_FORWARD_ONLY,
java.sql.ResultSet.CONCUR_READ_ONLY);
stmt.setFetchSize(50); //fetch only 50 records at a time
while with hibernate you would need the below code
Query query = session.createQuery(query);
query.setReadOnly(true);
query.setFetchSize(50);
ScrollableResults results = query.scroll(ScrollMode.FORWARD_ONLY);
// iterate over results
while (results.next()) {
Object row = results.get();
// process row then release reference
// you may need to flush() as well
}
results.close();
This allows you to stream over the result set, however Hibernate will still cache results in the Session, so you’ll need to call session.flush() every so often. If you are only reading data, you might consider using a StatelessSession, though you should read its documentation beforehand.
Analyze the database table locking impact when using this approach.
Short version of my question is:
PreparedStatement ps;
ps = connection.prepareStatement("Insert into T values (?)");
ps.setBoolean(1, true);
ps.executeUpdate();
What can be the reasons for this code sample to produce query with value wrapped in quotes?
Long version of my question is:
I have JavaEE application with plain JDBC for DB interactions and recently I noticed that there are some MySQLDataTruncation exceptions appearing in my logs. These exceptions were occurring on attempt to save entity into DB table which have boolean column defined as BIT(1). And it was because generated query looked like this:
Insert into T values ('1');
Note that value is wrapped with quotes. Query was logged from application with Log4J log.info(ps); statement.
Previous logs demonstrate that there where no quotes.
Furthermore, even MySQL server logs started to look different. Before this happened I had given pairs of records for each query executed:
12345 Prepare Insert into T values (?)
12345 Execute Insert into T values (1)
And after:
12345 Query Insert into T values ('1')
It is worth noting that those changes wasn`t a result of deploying new version of application or even restarting MySQL/Application server and code, responsible of query generation, is as straightforward as example in this question.
Application server restart fixed the issue for about 12 hours, and then it happened again. As a temporary solution I changed BIT columns to TINYINT
P.S. Examining both aplication and MySQL logs allowed to narrow down the time span when something went wrong to about 2 minutes, but there were nothing abnormal in the logs in this period.
P.P.S. Application server is Glassfish 2.1.1, MySQL server version is 5.5.31-1~dotdeb and MySQL Connector/J version is 5.0.3.
Well, it turned out it was actually an issue with unclosed prepared statements.
When opened statements count at MySQL server reached its allowed maximum, application was still able to continue working somehow, withoout producing sql error:
Error Code: 1461 Can’t create more than max_prepared_stmt_count statements
But in that mode it started to wrap boolean values with quotes, causing all my troubles affecting BIT(1) columns.
I am attempting to use zxJDBC to connect to a database running on SQL Server 2008 R2 (Express) and call a stored procedure, passing it a single parameter. I am using jython-standalone 2.5.3 and ideally do not want to have to install additional modules.
My test code is shown below.
The database name is CSM
Stored Procedure:
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
-- =============================================
-- Author: <Author,,Name>
-- Create date: <Create Date,,>
-- Description: <Description,,>
-- =============================================
CREATE PROCEDURE dbo.DUMMY
-- Add the parameters for the stored procedure here
#carrierId VARCHAR(50)
AS
BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;
-- Insert statements for procedure here
INSERT INTO dbo.carrier (carrierId, test)
VALUES (#carrierId, 'Success')
END
GO
Jython Script:
from com.ziclix.python.sql import zxJDBC
conn = None
try :
conn = zxJDBC.connect('jdbc:sqlserver://localhost\SQLEXPRESS', 'sa', 'password', 'com.microsoft.sqlserver.jdbc.SQLServerDriver')
cur = conn.cursor()
cur.callproc(('CSM','dbo','DUMMY'), ['carrier1'])
conn.commit()
except Exception, err :
print err
if conn:
conn.rollback()
finally :
if conn :
conn.close()
By using cur.execute() I have been able to verify that the above is successfully connecting to the database, and that I can query against it. However, I have thus far been unable to successfully call a stored procedure with parameters.
The documentation here(possibly out of date?) indicates that callproc() can be called with either a string or a tuple to identify the procedure. The example given -
c.callproc(("northwind", "dbo", "SalesByCategory"), ["Seafood", "1998"], maxrows=2)
When I attempt to use this method, I receive the following error
Error("Could not find stored procedure 'CSM.DUMMY'. [SQLCode: 2812], [SQLState: S00062]",)
It would appear that zxJDBC is neglecting to include the dbo part of the procedure identifier.
If I instead call callproc with "CSM.dbo.DUMMY" as the first argument then I receive this error
Error('An object or column name is missing or empty. For SELECT INTO statements, verify each column has a name. For other statements, look for empty alias names. Aliases defined as "" or [] are not allowed. Change the alias to a valid name. [SQLCode: 1038], [SQLState: S0004]',)
Using a profiler on the database whilst running my script shows that in the second case the following SQL is executed:
use []
go
So it would seem that when using a single string to identify the procedure, the database name is not correctly parsed out.
One of my trial and error attempts to fix this was to call callproc as follows:
cur.callproc(('CSM', '', 'dbo.DUMMY'), ['carrier1'])
This got me only as far as
Error("Procedure or function 'DUMMY' expects parameter '#carrierId', which was not supplied. [SQLCode: 201], [SQLState: S0004]",)
In this case what I think is happening is that zxJDBC attempts to call a system stored procedure (sp_proc_columns) to determine the required parameters for the stored procedure I want to call. My guess is that with the procedure identifier in the incorrect format above, zxJDBC does not get a valid/correct return and assumes no parameters are required.
So basically I am not a bit stuck for ideas as to how to get it to
Use the correct database name
Correctly determine the required parameters using sp_proc_columns
Call my stored procedure with the correct name
all at the same time.
I do have a workaround, which is to use something like
cur.execute('EXEC CSM.dbo.DUMMY ?', ['carrier1'])
However I feel like callproc() is the correct solution, and would likely produce cleaner code when I come to call stored procedures with large numbers of parameters.
If anyone can spot the mistake(s) that I am making, or knows that this is not ever going to work as I think then any input would be much appreciated.
Thanks
Edit
As suggested by i-one, I tried adding cur.execute('USE CSM') before calling my stored procedure (also removing the database name from the procedure call). This unfortunately produces the same Object or Column missing error as above. The profiler shows USE CSM being executed, followed by USE [] so it seems that callproc() always fires a USE statement before the procedure itself.
I have also experimented with turning on/off autocommit, to no avail.
Edit 2
Further information following comments/suggested solutions:
"SQLEXPRESS" in my connection string is the database instance name.
Using double quotes instead of single has no effect.
Including the database name in the connection string (via ;databaseName=CSM; as specified here) and omitting it from the callproc() call leads to the original error with a USE [] statement being fired.
Using callproc(('CSM', 'dbo', 'dbo.DUMMY'), ['carrier1']) gives me some progress but results in the error
Error("Procedure or function 'DUMMY' expects parameter '#carrierId', which was not supplied. [SQLCode: 201], [SQLState: S0004]",)
I'll attempt to investigate this further
Edit 3
Based on the queries I could see zxJDBC firing, I manually executed the following against my database:
use CSM
go
exec sp_sproc_columns_100 N'dbo.DUMMY',N'dbo',N'CSM',NULL,N'3'
go
This gave me an empty results set, which would seem to explain why zxJDBC isn't passing any parameters to the stored procedure - it doesn't think it needs to. I have yet to figure out why this is happening though.
Edit 4
To update the above, the empty result set is because the call should be
exec sp_sproc_columns_100 N'DUMMY',N'dbo',N'CSM',NULL,N'3'
This unfortunately brings me full circle as I can't remove the dbo owner from the stored procedure name in my callproc() call or the procedure won't be found at all.
Edit 5
Table definition as requested
CREATE TABLE [dbo].[carrier](
[carrierId] [varchar](50) NOT NULL,
[test] [varchar](50) NULL
) ON [PRIMARY]
Though completely unaware of the technologies used here (unless some minor knowledge of SQL Server), I will attempt an answer (please forgive me if my jython syntax is not correct. I am trying to outline possibilities here not exact code)
My first approach (found at this post) would be to try:
cur.execute("use CSM")
cur.callproc(("CSM","dbo","dbo.DUMMY"), ["carrier1"])
This must have to do with the fact that sa users always have the dbo as a default schema (described at this SO post)
If the above does not work I would also try to use the CSM database name in the JDBC url (this is very common when using JDBC for other databases) and then simply call one of the two below.
cur.callproc("DUMMY", ["carrier1"])
cur.callproc("dbo.DUMMY", ["carrier1"])
I hope this helps
Update: I quote the relevant part of the link that you can't view
>> Program calls a Stored Procedure - master.dbo.xp_fixeddrives on MS SQL Server
from com.ziclix.python.sql import zxJDBC
def getConnection():
url = "${DBServer.Url}"
user= "${DBServer.User}"
password = "${DBServer.Password}"
driver = "${DBServer.Driver}"
con = zxJDBC.connect(url, user, password, driver)
return con
try:
conn = getConnection()
print 'Connection successful'
cur = conn.cursor()
cur.execute("use master")
cur.callproc(("master", "dbo", "dbo.xp_fixeddrives"))
print cur.description
for a in cur.fetchall():
print a
finally:
cur.close()
conn.close()
print 'Connection closed'
The error you get when you specified the call function like above suggests that the parameter is not passed correctly. So please modify your stored procedure to take a default value and try to call with passing params = [None]. If you see that the call succeeds we must have done something right as far as specifying the database is concerned.
Btw: the most recent documentation suggests that you should be able to access it with your syntax.
As outlined in comments callproc will work only with SELECT. Try this approach instead:
cur.execute("exec CSM.dbo.DUMMY #Param1='" + str(Param1) + "', #carrierId=" + str(carrierID))
Please see this link for more detail.
Having strange performance issue using Hibernate 3.3.2GA behind JPA (and the rest of the Hibernate packages included in JBoss 5.)
I'm using Native Query, and assembling SQL into a prepared statement.
EntityManager em = getEntityManager(MY_DS);
final Query query = em.createNativeQuery(fullSql, entity.getClass());
The SQL has a lot of joins, but is actually very basic, with a single parameter. Like:
SELECT field1, field2, field3 FROM entity left join entity2 on... left join entity3 on
WHERE stringId like ?
and the query runs in under a second on MSSQL Studio.
If I add
query.setParameter(0, "ABC123%");
The query will pause for 9 seconds
2012-01-20 14:36:21 - TRACE: - AbstractBatcher.getPreparedStatement:(484) | preparing statement
2012-01-20 14:36:21 - TRACE: - StringType.nullSafeSet:(133) | binding 'ABC123%' to parameter: 1
2012-01-20 14:36:30 - DEBUG: - AbstractBatcher.logOpenResults:(382) | about to open ResultSet (open ResultSets: 0, globally: 0)
However, if I just replace the "?" with the value (making it not a Prepared Statement, but just a straight SQL query.
fullSql = fullSql.replace("?", "'ABC123%'");
the query will complete in less that a second.
I would really prefer to us a Prepared Statement (the input for the parameters is being extracted from user data) to prevent injection attacks.
Tracing down the slow point in the code, I arrived deep within the jtds-1.2.2 package. The offending line seems to be SharedSocket line 841 "getIn().readFully(hdrBuf);" Nothing really obvious there though...
private byte[] readPacket(byte buffer[])
throws IOException {
//
// Read rest of header
try {
getIn().readFully(hdrBuf);
} catch (EOFException e) {
throw new IOException("DB server closed connection.");
}
Arrived to through this stack...
at net.sourceforge.jtds.jdbc.SharedSocket.readPacket(SharedSocket.java:841)
at net.sourceforge.jtds.jdbc.SharedSocket.getNetPacket(SharedSocket.java:722)
at net.sourceforge.jtds.jdbc.ResponseStream.getPacket(ResponseStream.java:466)
at net.sourceforge.jtds.jdbc.ResponseStream.read(ResponseStream.java:103)
at net.sourceforge.jtds.jdbc.ResponseStream.peek(ResponseStream.java:88)
at net.sourceforge.jtds.jdbc.TdsCore.wait(TdsCore.java:3928)
at net.sourceforge.jtds.jdbc.TdsCore.executeSQL(TdsCore.java:1045)
at net.sourceforge.jtds.jdbc.TdsCore.microsoftPrepare(TdsCore.java:1178)
at net.sourceforge.jtds.jdbc.ConnectionJDBC2.prepareSQL(ConnectionJDBC2.java:657)
at net.sourceforge.jtds.jdbc.JtdsPreparedStatement.executeQuery(JtdsPreparedStatement.java:776)
at org.hibernate.jdbc.AbstractBatcher.getResultSet(AbstractBatcher.java:208)
at org.hibernate.loader.Loader.getResultSet(Loader.java:1808)
at org.hibernate.loader.Loader.doQuery(Loader.java:697)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:259)
at org.hibernate.loader.Loader.doList(Loader.java:2228)
at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2125)
at org.hibernate.loader.Loader.list(Loader.java:2120)
at org.hibernate.loader.custom.CustomLoader.list(CustomLoader.java:312)
at org.hibernate.impl.SessionImpl.listCustomQuery(SessionImpl.java:1722)
at org.hibernate.impl.AbstractSessionImpl.list(AbstractSessionImpl.java:165)
at org.hibernate.impl.SQLQueryImpl.list(SQLQueryImpl.java:175)
at org.hibernate.ejb.QueryImpl.getResultList(QueryImpl.java:67)
I'll leave this question and answer out here in case anyone has the same issue in the future.
The issue is in the way the JTDS drivers send the parameter strings to MSSQL. Apparently Java will attempt to send the parameters Unicode by default, and MSSQL will translate it to Ascii. Why that takes 9 seconds, I do not know.
Lot's of references to this out there, but nothing that helped my till I was able to isolate that it was an issue with the driver to MSSQL connection.
This link was helpful:
[http://server.pramati.com/blog/2010/06/02/perfissues-jdbcdrivers-mssqlserver/]
This is the string using the Microsoft driver.
jdbc:sqlserver://localhost\SQLEXPRESS;
DatabaseName=TESTDB;
sendStringParametersAsUnicode=false
You just need to get the sendStringParametersAsUnicode=false passed to your driver URL setup and you are good.
Check the query plans that SQL server is producing. Prepared statements can be especially problematic.
Let me explain...
If you do this:
SELECT field1, field2, field3 FROM entity left join entity2 on... left join entity3 on
WHERE stringId like 'ABC123%';
and you have an index on "stringId" SQL server knows it can use it.
However if you do this:
SELECT field1, field2, field3 FROM entity left join entity2 on... left join entity3 on
WHERE stringId like ?;
SQL server doesn't know it can use the index when it creates the prepared statement (as you could fill in the parameter with '%ABC123' instead of 'ABC123%') and thus may choose a completely different query plan.
And another answer for people potentially using Oracle with a similar Unicode problem...
Check to make sure someone hasn't set the property oracle.jdbc.defaultNChar=true
This is sometimes done to resolve unicode problems but it means all columns are treated as nvarchars. If you have an index on a varchar column, it won't be used because oracle has to use a function to convert the character encoding.