I have to run a jdbc update query using preparedstatement/statement without knowing the column type.
I have a query say ' update table set status=? where id=? '
and i am getting a map of values like {("status"="123"), ("id"="546")}
Now I don't know the column type, is there any generic way to run this query using jdbc?
Instead of running - ps.setString(1,map.get(("status"));
beacause i don't know the column type of status field in DB (it may be a int also)
Please help me in solving this without using spring jdbc templates.
ps.setString(1,map.get(("status")) will work for integer also, you just has to take care that value you are putting in integer column is of int type.
Following code explains that:
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
public class SOJDBC
{
public static void main(String rgs[])
{
Connection con = DBConnection.getConnection("TEMP");
try
{
PreparedStatement pstmt = con.prepareStatement("insert into STUDENT(ROLLNO,NAME,AGE) values(?,?,?)");
pstmt.setString(1, "1"); //column type is integer, will work because the value is of int type
pstmt.setString(2, "Bhushan");
pstmt.setString(3, "25"); //column type is integer, will work because the value is of int type
pstmt.executeUpdate();
}
catch (SQLException e)
{
e.printStackTrace();
}
}
}
Related
I have inherited an old Oracle 12c database, which I'm running on a local Oracle 19c server. The database contains the following Java Stored Procedure
create or replace and compile java source named fill_share_content as
import java.io.*;
import java.sql.*;
public class Fill_Share_Content
{
public static void execute(String directory) throws SQLException
{
File path = new File( directory );
String[] list = path.list();
String separator = path.separator;
for(int i = 0; i < list.length; i++)
{
String filename = list[i];
File datei = new File( directory + separator + filename );
if ( datei.isFile() )
{
Timestamp filedate = new Timestamp( datei.lastModified() );
#sql { insert into Share_Content (filename, filedate) values (:filename, :filedate) };
}
}
}
};
/
The problem occurs when attempting to execute the statement to create and compile the Java SP: line 20
#sql { insert into Share_Content (filename, filedate) values (:filename, :filedate) };
throws an error
error: illegal character: '#'
Generally I am able to create, compile and execute Java Stored Procedures on the database. Questions:
What is the meaning of the line starting with the hash sign? I am not familiar with such a construct in Java, something specific to Java stored procedures in Oracle?
How can I get I create and compile the Java stored procedure? Allegedly the code is already running on another instance, so the code should work.
The code is SQLJ and is documented here.
However, from Oracle 12.2, Oracle does not support running SQLJ.
You need to convert the SQLJ code to JDBC if you want to run it in Oracle 19.
This should give you a start:
CREATE AND COMPILE JAVA SOURCE NAMED fill_share_content as
import java.io.*;
import java.sql.*;
import oracle.jdbc.driver.OracleDriver;
public class Fill_Share_Content
{
public static void execute(String directory) throws SQLException
{
Connection con = null;
try {
OracleDriver ora = new OracleDriver();
con = ora.defaultConnection();
} catch (SQLException e) {
return;
}
Timestamp filedate = new Timestamp(System.currentTimeMillis());
PreparedStatement ps = con.prepareStatement(
"insert into Share_Content (filename, filedate) values (:filename, :filedate)"
);
ps.setString(1, directory);
ps.setTimestamp(2, filedate);
ps.execute();
}
};
/
db<>fiddle here
Apache beam provides the JDBCIO connector to connect to CloudSql postgreSQL. My job reads an event from pub/sub. The event body is as below:
tableName,
list<value>
I need to write to the table based on the table name that I get in from my message.
The JDBCIO has prepared statement which will let me parameterize the values in my insert query. But I need to generate the insert query dynamically based on the information present in the event.
pipeline
.apply(PubsubIO.readStrings().fromSubscription())
.apply(convertToKV())
.apply(JdbcIO.<List<String>>>write()
.withDataSourceConfiguration(JdbcIO.DataSourceConfiguration.create(
"com.mysql.jdbc.Driver", "jdbc:mysql://hostname:3306/mydb")
.withUsername("username")
.withPassword("password"))
.withStatement("insert into Person values(?, ?)")
.withPreparedStatementSetter(new JdbcIO.PreparedStatementSetter<KV<Integer, String>>() {
public void setParameters(KV<Integer, String> element, PreparedStatement query)
throws SQLException {
i=0
for each element in list
query.setInt(i, element.get(i);
i++;
}
})
);
I should be able to create the SQL statement dynamically based on the input event from the pcollection.
My select statement should be dynamically generated based on the list value and the table name. Please let me know whether we can do this or not.
Update:-
im trying to manually call the jdbc driver inside the parDo function but getting the below error.
No suitable driver found for jdbcURL.
Please let me know if im missing anyting:
#Setup
public void doAnyRequiredSetup() throws SQLException
{
LoggingContextUtil.installContext(loggingContext);
connection=DriverManager.getConnection(JdbcUrl,user,password);
statement=connection.createStatement();
if (LOGGER.isDebugEnabled()) {
LOGGER.debug("In doAnyRequiredSetup logging Context is now set and JDBC connection is .");
}
}
#SuppressWarnings("unchecked")
#ProcessElement
public void processElement(ProcessContext context)
{
JsonNode element=context.element();
try {
String query=formatQuery(baseQuery);
boolean result=statement.execute(query);
if(LOGGER.isDebugEnabled()) {
LOGGER.debug("Executed query : "+query+" and the result is "+ result);
}
} catch (IllegalArgumentException | SQLException e) {
ErrorMessage em = new ErrorMessage(element.toString(), "Insert Query Failed", e.getMessage());
context.output(ValidateTagHelper.FAILURE_TAG,em);
}
}
You can not have dynamic queries on JdbcIO based on the input elements.
The ParDo has to reset as you like, you can rewrite your ParDo in which you would call the JDBC driver manually.
If find this other workaround, you can split the input PColleciton into multiple outputs. That will work if your use case is limited to some predefined set of queries that you can choose from based on the input. This way you split the input into multiple PCollections and then attach differently configured IOs to each.
https://cloud.google.com/blog/products/gcp/guide-to-common-cloud-dataflow-use-case-patterns-part-1
You can try to read pubsub messages with attributes and in attributes, you can pass the table name and values in the form of Key-value pair.
PCollection<PubsubMessage> pubsubMessage = pipeline
.apply(PubsubIO.readMessagesWithAttributes().fromSubscription("")
I want to get subquery from impala table as one dataset.
Code like this:
String subQuery = "(select to_timestamp(unix_timestamp(now())) as ts from my_table) t"
Dataset<Row> ds = spark.read().jdbc(myImpalaUrl, subQuery, prop);
But result is error:
Caused by: java.sql.SQLDataException: [Cloudera][JDBC](10140) Error converting value to Timestamp.
I can use unix_timestamp function,but to_timestmap failed, why?
I found code in org.apache.spark.sql.execution.datasources.jdbc.JDBC.compute() exists some problem:
sqlText = s"SELECT $columnList FROM ${options.table} $myWhereClause"
$columList contains " like "col_name" , when I delete " it work fine.
I solve this problem by add dialect, default dialect will add "" to column name,
JdbcDialect ImpalaDialect = new JdbcDialect(){
#Override
public boolean canHandle(String url) {
return url.startsWith("jdbc:impala") || url.contains("impala");
}
#Override
public String quoteIdentifier(String colName) {
return colName;
}
};
JdbcDialects.registerDialect(ImpalaDialect);
I'm so close in solving this question but I'm apparently missing something. My requirement is to call a stored procedure in Oracle from JDBC. The stored procedure takes 1 user-defined Oracle object as INput and another user-defined Oracle object as OUTput. The INput and OUTput objects have mix of both primitive Oracle data types and collection of another set of user-defined objects. I'm successfully able to call the stored procedure and get results back as long as I set NULL for the collection types in the INput and OUTput objects. If I try to create ArrayDescriptor for the list of Oracle objects to send it to the stored procedure I keep hitting roadblocks. So I need help with figuring out how to set the Array to the INput object and set that to CallableStatement. Please note, I am aware of how I can send the primitive type and array as direct inputs to the stored procedure. But I do not want to go that way as we later have to send 10 additional fields to the procedure, I do not want to add them to method signature. Here's the list of classes. Also, there is no compilation errors for the code below.
Package in oracle:
CREATE OR REPLACE PACKAGE testPkg AS
PROCEDURE spGetTestData (
TESTDATA_IN IN TESTDATA_IN_OBJ,
TESTDATA_OUT OUT TESTDATA_OUT_OBJ
);
END;
INput object for the stored procedure:
CREATE OR REPLACE TYPE TESTDATA_IN_OBJ AS OBJECT(
testStr1 VARCHAR2(5),
arrObj1 ARR_OBJ_1_NT);
Array Object as part of INput Object:
create or replace TYPE ARR_OBJ_1_NT AS TABLE OF ARR_OBJ_1_OBJ;
UserDefined Object part of INput Object:
CREATE OR REPLACE TYPE ARR_OBJ_1_OBJ AS OBJECT
(
teststr VARCHAR2(14),
testNumber NUMBER(4),
);
TestDataINObj.java:
import java.sql.Array;
import java.sql.SQLData;
import java.sql.SQLException;
import java.sql.SQLInput;
import java.sql.SQLOutput;
public class TestDataINObj implements SQLData
{
private String sql_type = "TESTDATA_IN_OBJ";
protected String testStr1;
protected Array arrObj1;
#Override
public String getSQLTypeName() throws SQLException
{
return this.sql_type;
}
// getter and setter for fields
#Override
public void readSQL(SQLInput stream, String typeName) throws SQLException
{
this.sql_type=typeName;
this.testStr1 = stream.readString();
this.arrObj1 = stream.readArray();
}
#Override
public void writeSQL(SQLOutput stream) throws SQLException
{
stream.writeString(this.testStr1);
stream.writeArray(this.arrObj1);
}
}
TestDataINObjConverter.java:
public class TestDataINObjConverter
{
public static TestDataINObj convertPOJOToDBInObj(Connection connection)
throws SQLException
{
TestDataINObj testDataINObj = new TestDataINObj();
testDataINObj.setTestStr1("some string");
ArrObj1NT[] ArrObj1NTList = ArrObj1NTConverter.convertPOJOToDBObj(); // this will return Java array of ArrObj1NT class
testDataINObj.setArrObj1(getOracleArray("ARR_OBJ_1_NT",connection, ArrObj1NTList));
return testDataINObj;
}
private static Array getOracleArray(final String typeName, Connection connection, ArrObj1NT[] ArrObj1NTList) throws SQLException
{
if (typeName == null)
{
return null;
}
Array oracleArray = new ARRAY(new ArrayDescriptor(typeName, connection), connection, ArrObj1NTList);
return oracleArray;
}
Code that actually executes call to stored procedure:
... //code to get connection
..// connection is of type T4CConnection
Map typeMap = connection.getTypeMap();
typeMap.put("TESTDATA_IN_OBJ", TestDataINObj.class);
typeMap.put("TESTDATA_OUT_OBJ", TestDataOUTObj.class);
typeMap.put("ARR_OBJ_1_NT", ArrObj1NT.class);
TestDataINObj testDataINObj = TestDataINObjConverter.convertPOJOToDBInObj(connection);
getMetaDataCallableStatement = connection.prepareCall("begin " + "testPkg" + ".spGetTestData (?,?);"+ " end;");
getMetaDataCallableStatement.setObject(1, testDataINObj);
getMetaDataCallableStatement.registerOutParameter(2, Types.STRUCT, "TESTDATA_OUT_OBJ");
rs = getMetaDataCallableStatement.executeQuery();
TestDataOUTObj testDataOUTObj = (TestDataOUTObj) getMetaDataCallableStatement.getObject(2, typeMap);
Miscellaneous:
1. The objects are declared in Schema level and is available for the db user to access it.
2. I've not included all of the corresponding Java objects here as it will take more space. They implement SQLData interface and their type names match with DB names. The read and writeSQL methods uses getString, getArray and corresponding setter methods.
This is a very old approach, why are you not using "Oradata" and "Oradatum" interface?
It will save lot of effort.
Your approach leaves a lot of scopr for error, you will have to read the stream in proper manner and check for ordering of fields yourself which can be tricky. Oradata approach will do that for you.
Coming to your approach, Your code is not very clear.
But just to give an overview, StructDescriptor will map to oracle record type and ArrayDescriptor will map to oracle table type, from your code i am confused about whta you are trying to achieve.
I can help if you can make it more clear.
Is there any way I can get resultset object from one of jdbctemplate query methods?
I have a code like
List<ResultSet> rsList = template.query(finalQuery, new RowMapper<ResultSet>() {
public ResultSet mapRow(ResultSet rs, int rowNum) throws SQLException {
return rs;
}
}
);
I wanted to execute my sql statement stored in finalQuery String and get the resultset. The query is a complex join on 6 to 7 tables and I am select 4-5 columns from each table and wanted to get the metadata of those columns to transform data types and data to downstream systems.
If it is a simple query and I am fetching form only one table I can use RowMapper#mapRow and inside that maprow method i can call ResultsetExtractor.extractData to get list of results; but in this case I have complex joins in my query and I am trying to get resultset Object and from that resultset metadata...
The above code is not good because for each result it will return same resultset object and I dont want to store them in list ...
Once more thing is if maprow is called for each result from my query will JDBCTemplate close the rs and connection even though my list has reference to RS object?
Is there any simple method like jdbcTemplate.queryForResultSet(sql) ?
Now I have implemented my own ResultSet Extractor to process and insert data into downstream systems
sourceJdbcTemplate.query(finalQuery, new CustomResultSetProcessor(targetTable, targetJdbcTemplate));
This CustomResultSetProcessor implements ResultSetExtractor and in extractData method I am calling 3 different methods 1 is get ColumnTypes form rs.getMetaData() and second is getColumnTypes of target metadata by running
SELECT NAME, COLTYPE, TBNAME FROM SYSIBM.SYSCOLUMNS WHERE TBNAME ='TABLENAME' AND TABCREATOR='TABLE CREATOR'
and in 3rd method I am building the insert statement (prepared) form target columntypes and finally calling that using
new BatchPreparedStatementSetter()
{
#Override
public void setValues(PreparedStatement insertStmt, int i) throws SQLException{} }
Hope this helps to others...
Note that the whole point of Spring JDBC Template is that it automatically closes all resources, including ResultSet, after execution of callback method. Therefore it would be better to extract necessary data inside a callback method and allow Spring to close the ResultSet after it.
If result of data extraction is not a List, you can use ResultSetExtractor instead of RowMapper:
SomeComplexResult r = template.query(finalQuery,
new ResultSetExtractor<SomeComplexResult>() {
public SomeResult extractData(ResultSet) {
// do complex processing of ResultSet and return its result as SomeComplexResult
}
});
Something like this would also work:
Connection con = DataSourceUtils.getConnection(dataSource); // your datasource
Statement s = con.createStatement();
ResultSet rs = s.executeQuery(query); // your query
ResultSetMetaData rsmd = rs.getMetaData();
Although I agree with #axtavt that ResultSetExtractor is preferred in Spring environment, it does force you to execute the query.
The code below does not require you to do so, so that the client code is not required to provide the actual arguments for the query parameters:
public SomeResult getMetadata(String querySql) throws SQLException {
Assert.hasText(querySql);
DataSource ds = jdbcTemplate.getDataSource();
Connection con = null;
PreparedStatement ps = null;
try {
con = DataSourceUtils.getConnection(ds);
ps = con.prepareStatement(querySql);
ResultSetMetaData md = ps.getMetaData(); //<-- the query is compiled, but not executed
return processMetadata(md);
} finally {
JdbcUtils.closeStatement(ps);
DataSourceUtils.releaseConnection(con, ds);
}
}