Oracle® Database JDBC Developer's Guide and Reference 10g Release 2 (10.2) Part Number B14355-02 |
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This chapter describes data access in oracle.sql.*
formats, as opposed to standard Java formats. The oracle.sql.*
formats are a key factor of the Oracle Java Database Connectivity (JDBC) extensions, offering significant advantages in efficiency and precision in manipulating SQL data.
Using oracle.sql.*
formats involves casting your result sets and statements to OracleResultSet
, OracleStatement
, OraclePreparedStatement
, and OracleCallableStatement
, as appropriate, and using the getOracleObject
, setOracleObject
, get
XXX
, and set
XXX
methods of these classes, where XXX
corresponds to the types in the oracle.sql
package.
This chapter covers the following topics:
The Oracle JDBC drivers support standard JDBC types as well as Oracle-specific data types. This section documents standard and Oracle-specific SQL-Java default type mappings. This section contains the following topics:
Table 13-1 shows the default mappings between SQL data types, JDBC type codes, standard Java types, and Oracle extended types.
The SQL Data Types column lists the SQL types that exist in Oracle Database 10g. The JDBC Type Codes column lists data type codes supported by the JDBC standard and defined in the java.sql.Types
class or by Oracle in the oracle.jdbc.OracleTypes
class. For standard type codes, the codes are identical in these two classes.
The Standard Java Types column lists standard types defined in the Java language. The Oracle Extension Java Types column lists the oracle.sql.*
Java types that correspond to each SQL data type in the database. These are Oracle extensions that let you retrieve all SQL data in the form of a oracle.sql.*
Java type. Manipulating SQL data as oracle.sql.*
data types minimizes conversions, improving performance and eliminating conversion losses.
See Also:
"Package oracle.sql"Table 13-1 Default Mappings Between SQL Types and Java Types
SQL Data Types | JDBC Type Codes | Standard Java Types | Oracle Extension Java Types |
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STANDARD JDBC 1.0 TYPES: |
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STANDARD JDBC 2.0 TYPES: |
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user-defined object |
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user-defined reference |
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user-defined collection |
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ORACLE EXTENSIONS: |
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NA |
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NA |
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Note:
For database versions, such as 8.1.7, which do not support theTIMESTAMP
data type, TIMESTAMP
is mapped to DATE
.This section provides further detail regarding mappings for NUMBER
and user-defined types.
NUMBER Types
For the different type codes that an Oracle NUMBER
value can correspond to, call the getter routine that is appropriate for the size of the data for mapping to work properly. For example, call getByte
to get a Java tinyint
value for an item x, where -128 < x < 128.
User-Defined Types
User-defined types, such as objects, object references, and collections, map by default to weak Java types, such as java.sql.Struct
, but alternatively can map to strongly typed custom Java classes. Custom Java classes can implement one of two interfaces:
The standard java.sql.SQLData
The Oracle-specific oracle.sql.ORAData
When JDBC programs retrieve SQL data into Java, you can use standard Java types, or you can use types of the oracle.sql
package. This section covers the following topics:
The Oracle data types in oracle.sql
store data in the same bit format as used by the database. In versions of the Oracle JDBC drivers prior to Oracle Database 10g, the Oracle data types were generally more efficient. The Oracle Database 10g JDBC drivers were substantially updated. As a result, in most cases the standard Java types are preferred to the data types in oracle.sql
. In particular, java.lang.String
is much more efficient than oracle.sql.CHAR
.
In general, Oracle recommends that you use the Java standard types. The exceptions to this are:
Use the oracle.sql.OraData
rather than the java.sql.SqlData
if the OraData functionality better suits your needs.
Use oracle.sql.NUMBER
rather than java.lang.Double
if you need to retain the exact values of floating point numbers. Oracle NUMBER
is a decimal representation and Java Double
and Float
are binary representations. Conversion from one format to the other can result in slight variations in the actual value represented. Additionally, the range of values that can be represented using the two formats is different.
Use oracle.sql.DATE
or oracle.sql.TIMESTAMP
rather than java.sql.Date
or java.sql.Timestamp
if you are using JDK 5.0 or earlier versions or require maximum performance. You may also use the oracle.sql
data type if you want to read many date values or compute or display only a small percentage. Due to a bug in all versions of Java prior to JDK 5.1, construction of java.lang.Date
and java.lang.Timestamp
objects is slow, especially in multithreaded environments. This bug is fixed in JDK 5.1.
Note:
If you convert anoracle.sql
data type to a Java standard data type, then the benefits of using the oracle.sql
data type are lost.Java represents a SQL NULL
datum by the Java value null
. Java data types fall into two categories: primitive types, such as byte
, int
, and float
, and object types, such as class instances. The primitive types cannot represent null
. Instead, they store null
as the value zero, as defined by the JDBC specification. This can lead to ambiguity when you try to interpret your results.
In contrast, Java object types can represent null
. The Java language defines an object wrapper type corresponding to every primitive type that can represent null
. The object wrapper types must be used as the targets for SQL data to detect SQL NULL
without ambiguity.
You cannot use a relational operator to compare NULL
values with each other or with other values. For example, the following SELECT
statement does not return any row even if the COMM
column contains one or more NULL
values.
PreparedStatement pstmt = conn.prepareStatement( "SELECT * FROM EMP WHERE COMM = ?"); pstmt.setNull(1, java.sql.Types.VARCHAR);
The next example shows how to compare values for equality when some return values might be NULL
. The following code returns all the ENAMES
from the EMP
table that are NULL
, if there is no value of 100 for COMM
.
PreparedStatement pstmt = conn.prepareStatement("SELECT ENAME FROM EMP WHERE COMM =? OR ((COMM IS NULL) AND (? IS NULL))"); pstmt.setBigDecimal(1, new BigDecimal(100)); pstmt.setNull(2, java.sql.Types.VARCHAR);
The JDBC Statement
object returns an OracleResultSet
object, typed as a java.sql.ResultSet
. If you want to apply only standard JDBC methods to the object, then keep it as a ResultSet
type. However, if you want to use the Oracle extensions on the object, then you must cast it to OracleResultSet
. All of the Oracle ResultSet
extensions are in the oracle.jdbc.OracleResultSet
interface and all the Statement
extensions are in the oracle.jdbc.OracleStatement
interface.
For example, assuming you have a standard Statement
object stmt
, do the following if you want to use only standard JDBC ResultSet
methods:
ResultSet rs = stmt.executeQuery("SELECT * FROM emp");
If you need the extended functionality provided by the Oracle extensions to JDBC, you can select the results into a standard ResultSet
variable and then cast that variable to OracleResultSet
later.
Similarly, when you use executeQuery
to run a stored procedure using a callable statement, the returned object is an OracleCallableStatement
. The type of the return value of executeQuery(
) is java.sql.CallableStatement
. If your application needs only the standard JDBC methods, you need not cast the variable. However, to take advantage of the Oracle extensions, you must cast the variable to OracleCallableStatement
. Similar rules apply to prepareStatement
, prepareCall
, and so on.
Key extensions to the result set and statement classes include the getOracleObject
and setOracleObject
methods, used to access and manipulate data in oracle.sql.*
formats.
This section describes get
and set
methods, particularly the JDBC standard getObject
and setObject
methods and the Oracle-specific getOracleObject
and setOracleObject
methods, and how to access data in oracle.sql.*
format compared with Java format.
Although there are specific get
XXX
methods for all the Oracle SQL types, you can use the general get
methods for convenience or simplicity, or if you are not certain in advance what type of data you will receive.
This section covers the following topics:
Note:
You cannot qualify a column name with a table name and pass it as a parameter to theget
XXX
method. For example:
ResultSet rset = stmt.executeQuery("SELECT emp.deptno, dept.deptno FROM emp, dept"); rset.getInt("emp.deptno");
The getInt
method in the preceding code will throw an exception. To uniquely identify the columns in the get
XXX
method, you can either use column index or specify column aliases in the query and use these aliases in the get
XXX
method.
The standard getObject
method of a result set or callable statement has a return type of java.lang.Object
. The class of the object returned is based on its SQL type, as follows:
For SQL data types that are not Oracle-specific, getObject
returns the default Java type corresponding to the SQL type of the column, following the mapping in the JDBC specification.
For Oracle-specific data types, getObject
returns an object of the appropriate oracle.sql.*
class, such as oracle.sql.ROWID
.
For Oracle database objects, getObject
returns a Java object of the class specified in your type map. Type maps specify a mapping from database named types to Java classes. The getObject(
parameter_index
)
method uses the default type map of the connection. The getObject(
parameter_index
,
map
)
enables you to pass in a type map. If the type map does not provide a mapping for a particular Oracle object, then getObject
returns an oracle.sql.STRUCT
object.
If you want to retrieve data from a result set or callable statement as an oracle.sql.*
object, then you must follow a special process. For a ResultSet
, you must cast the result set itself to oracle.jdbc.OracleResultSet
and then call getOracleObject
instead of getObject
. The same applies to CallableStatement
and oracle.jdbc.OracleCallableStatement
.
The return type of getOracleObject
is oracle.sql.Datum
. The actual returned object is an instance of the appropriate oracle.sql.*
class. The method signature is:
public oracle.sql.Datum getOracleObject(int parameter_index)
When you retrieve data into a Datum
variable, you can use the standard Java instanceof
operator to determine which oracle.sql.*
type it really is.
Example: Using getOracleObject with a ResultSet
The following example creates a table that contains a column of CHAR
data and a column containing a BFILE
locator. A SELECT
statement retrieves the contents of the table as a result set. The getOracleObject
then retrieves the CHAR
data into the char_datum
variable and the BFILE
locator into the bfile_datum
variable. Note that because getOracleObject
returns a Datum
object, the return values must be cast to CHAR
and BFILE
, respectively.
stmt.execute ("CREATE TABLE bfile_table (x VARCHAR2 (30), b BFILE)"); stmt.execute ("INSERT INTO bfile_table VALUES ('one', BFILENAME ('TEST_DIR', 'file1'))"); ResultSet rset = stmt.executeQuery ("SELECT * FROM bfile_table"); while (rset.next ()) { CHAR char_datum = (CHAR) ((OracleResultSet)rset).getOracleObject (1); BFILE bfile_datum = (BFILE) ((OracleResultSet)rset).getOracleObject (2); ... }
Example: Using getOracleObject in a Callable Statement
The following example prepares a call to the procedure myGetDate
, which associates a character string with a date. The program passes "SCOTT"
to the prepared call and registers the DATE
type as an output parameter. After the call is run, getOracleObject
retrieves the date associated with "SCOTT"
. Note that because getOracleObject
returns a Datum
object, the results are cast to DATE
.
OracleCallableStatement cstmt = (OracleCallableStatement)conn.prepareCall ("begin myGetDate (?, ?); end;"); cstmt.setString (1, "SCOTT"); cstmt.registerOutParameter (2, Types.DATE); cstmt.execute (); DATE date = (DATE) ((OracleCallableStatement)cstmt).getOracleObject (2); ...
Table 13-2 lists the underlying return types for the getObject
and getOracleObject
methods for each Oracle SQL type.
Keep in mind the following when you use these methods:
getObject
always returns data into a java.lang.Object
instance
getOracleObject
always returns data into an oracle.sql.Datum
instance
You must cast the returned object to use any special functionality.
Table 13-2 getObject and getOracleObject Return Types
Oracle SQL Type | getObject Underlying Return Type | getOracleObject Underlying Return Type |
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(not supported) |
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Oracle object |
class specified in type map or |
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Oracle object reference |
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collection (varray or nested table) |
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Footnote 1 ResultSet.getObject
returns java.sql.Timestamp
only if the oracle.jdbc.J2EE13Compliant
connection property is set to TURE
, else the method returns oracle.sql.TIMESTAMP
.
Note:
TheResultSet.getObject
method returns java.sql.Timestamp
for the TIMESTAMP
SQL type, only when the connection property oracle.jdbc.J2EE13Compliant
is set to TRUE
. This property has to be set when the connection is obtained. If this connection property is not set or if it is set after the connection is obtained, then the ResultSet.getObject
method returns oracle.sql.TIMESTAMP
for the TIMESTAMP
SQL type.
The oracle.jdbc.J2EE13Compliant
connection property can also be set without changing the code in the following ways:
Including the classes12dms.jar
and ojdbc14dms.jar
files in CLASSPATH
. These files set oracle.jdbc.J2EE13Compliant
to TRUE
by default. These files are located in $ORACLE_HOME/jdbc/lib
.
Setting the system property by calling the java
command with the flag -Doracle.jdbc.J2EE13Compliant=true
. For example,
java -Doracle.jdbc.J2EE13Compliant=true ...
When the J2EE13Compliant
is set to TRUE
the behaviour is as in Table B-3 of the JDBC specification.
See Also:
Table A-1, "Valid SQL Data Type-Java Class Mappings", for information on type compatibility between all SQL and Java types.Standard JDBC provides a get
XXX
for each standard Java type, such as getByte
, getInt
, getFloat
, and so on. Each of these returns exactly what the method name implies.
In addition, the OracleResultSet
and OracleCallableStatement
classes provide a full complement of get
XXX
methods corresponding to all the oracle.sql.*
types. Each get
XXX
method returns an oracle.sql.
XXX
object. For example, getROWID
returns an oracle.sql.ROWID
object.
There is no performance advantage in using the specific get
XXX
methods. However, they do save you the trouble of casting, because the return type is specific to the object being returned.
This section covers the following topics:
Table 13-3 summarizes the return types for each get
XXX
method and specifies which are Oracle extensions under Java Development Kit (JDK) 1.2.x. You must cast the returned object to OracleResultSet
or OracleCallableStatement
to use methods that are Oracle extensions.
Table 13-3 Summary of getXXX Return Types
Method | Return Type (type in method signature) | Type of returned object | Oracle Ext for JDK 1.2.x? |
---|---|---|---|
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No |
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Yes |
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No |
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Yes |
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Yes |
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No |
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No |
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No |
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Yes |
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No |
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No |
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No |
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Yes |
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No |
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No |
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Yes |
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No |
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Yes |
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No |
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No |
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No |
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Yes |
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Yes |
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No |
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Yes |
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subclasses of |
Yes |
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Yes |
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No |
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Yes |
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Yes |
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No |
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No |
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Yes |
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No |
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No |
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Yes |
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Yes |
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Yes |
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No |
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No |
This section provides additional details about some get
XXX
methods.
getBigDecimal
JDBC 2.0 simplified method signatures for the getBigDecimal
method. The previous input signatures were:
(int columnIndex, int scale) or (String columnName, int scale)
The simplified input signature is:
(int columnIndex) or (String columnName)
The scale
parameter, used to specify the number of digits to the right of the decimal, is no longer necessary. The Oracle JDBC drivers retrieve numeric values with full precision.
getBoolean
Because there is no BOOLEAN
database type, when you use getBoolean
a data type conversion always occurs. The getBoolean
method is supported only for numeric columns. When applied to these columns, getBoolean
interprets any zero value as false
and any other value as true
. When applied to any other sort of column, getBoolean
raises the exception java.lang.NumberFormatException
.
The return type of getObject
is java.lang.Object
. The returned value is an instance of a subclass of java.lang.Object
. Similarly, the return type of getOracleObject
is oracle.sql.Datum
, and the class of the returned value is a subclass of oracle.sql.Datum
. You normally cast the returned object to the appropriate class to use particular methods and functionality of that class.
In addition, you have the option of using a specific get
XXX
method instead of the generic getObject
or getOracleObject
methods. The get
XXX
methods enable you to avoid casting, because the return type of get
XXX
corresponds to the type of object returned. For example, the return type of getCLOB
is oracle.sql.CLOB
, as opposed to java.lang.Object
.
Example of Casting Return Values
This example assumes that you have fetched data of the NUMBER
type as the first column of a result set. Because you want to manipulate the NUMBER
data without losing precision, cast your result set to OracleResultSet
and use getOracleObject
to return the NUMBER
data in oracle.sql.*
format. If you do not cast your result set, then you have to use getObject
, which returns your numeric data into a Java Float
and loses some of the precision of your SQL data.
The getOracleObject
method returns an oracle.sql.NUMBER
object into an oracle.sql.Datum
return variable unless you cast the output. Cast the getOracleObject
output to oracle.sql.NUMBER
if you want to use a NUMBER
return variable and any of the special functionality of that class.
NUMBER x = (NUMBER)ors.getOracleObject(1);
Alternatively, you can return the object into a generic oracle.sql.Datum
return variable and cast it later when you use NUMBER
-specific methods.
Datum rawdatum = ors.getOracleObject(1); ... CharacterSet cs = ((NUMBER) rawdatum).FIXME();
This uses the FIXME
method of oracle.sql.NUMBER
. The FIXME
method is not defined on oracle.sql.Datum
and would not be reachable without the cast.
Just as there is a standard getObject
and Oracle-specific getOracleObject
in result sets and callable statements, there are also standard setObject
and Oracle-specific setOracleObject
methods in OraclePreparedStatement
and OracleCallableStatement
. The setOracleObject
methods take oracle.sql.*
input parameters.
To bind standard Java types to a prepared statement or callable statement, use the setObject
method, which takes a java.lang.Object
as input. The setObject
method does support a few of the oracle.sql.*
types. However, the method has been implemented so that you can enter instances of the oracle.sql.*
classes that correspond to the following JDBC standard types: Blob
, Clob
, Struct
, Ref
, and Array
.
To bind oracle.sql.*
types to a prepared statement or callable statement, use the setOracleObject
method, which takes a subclass of oracle.sql.Datum
as input. To use setOracleObject
, you must cast your prepared statement or callable statement to OraclePreparedStatement
or OracleCallableStatement
.
Example of Using setObject and setOracleObject
For a prepared statement, the setOracleObject
method binds the oracle.sql.CHAR
data represented by the charVal
variable to the prepared statement. To bind the oracle.sql.*
data, the prepared statement must be cast to OraclePreparedStatement
. Similarly, the setObject
method binds the Java String
data represented by the variable strVal
.
PreparedStatement ps= conn.prepareStatement("text_of_prepared_statement"); ((OraclePreparedStatement)ps).setOracleObject(1,charVal); ps.setObject(2,strVal);
As with the get
XXX
methods, there are several specific set
XXX
methods. Standard set
XXX
methods are provided for binding standard Java types, and Oracle-specific set
XXX
methods are provided for binding Oracle-specific types.
Similarly, there are two forms of the setNull
method:
void setNull(int
parameterIndex,
int
sqlType
)
This is specified in the standard java.sql.PreparedStatement
interface. This signature takes a parameter index and a SQL type code defined by the java.sql.Types
or oracle.jdbc.OracleTypes
class. Use this signature to set an object other than a REF
, ARRAY
, or STRUCT
to NULL
.
void setNull(int
parameterIndex
, int
sqlType
, String
sql_type_name
)
With JDBC 2.0, this signature is also specified in the standard java.sql.PreparedStatement
interface. This method takes a SQL type name in addition to a parameter index and a SQL type code. Use this method when the SQL type code is java.sql.Types.REF
, ARRAY
, or STRUCT
. If the type code is other than REF
, ARRAY
, or STRUCT
, then the given SQL type name is ignored.
Similarly, the registerOutParameter
method has a signature for use with REF
, ARRAY
, or STRUCT
data:
void registerOutParameter (int parameterIndex, int sqlType, String sql_type_name)
Binding Oracle-specific types using the appropriate setXXX
methods, instead of the methods used for binding standard Java types, may offer some performance advantage.
This section covers the following topics:
Table 13-4 summarizes the input types for all the setXXX
methods and specifies which are Oracle extensions under JDK 1.2.x. To use methods that are Oracle extensions, you must cast your statement to OraclePreparedStatement
or OracleCallableStatement
.
Table 13-4 Summary of setXXX Input Parameter Types
Method | Input Parameter Type | Oracle Ext for JDK 1.2.x? |
---|---|---|
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No |
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Yes |
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No |
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Yes |
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Yes |
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No |
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Yes |
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Yes |
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No |
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No |
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Yes |
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No |
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No |
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No |
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Yes |
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No |
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No |
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Yes |
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No |
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Yes |
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No |
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Yes |
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No |
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No |
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Yes |
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Yes |
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No |
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Yes |
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Yes |
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No |
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Yes |
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Yes |
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No |
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No |
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Yes |
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No |
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No |
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Yes |
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Yes |
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Yes |
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No |
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No |
Table 13-5 lists size limitations for the setBytes
and setString
methods for SQL binds.
Note:
These limitations do not apply to PL/SQL binds.Table 13-5 Size Limitations for setBytes and setString Methods
Method Name | Size Limit |
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2000 bytes |
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4000 bytes |
See Also:
"Using Streams to Avoid Limits on setBytes and setString", for information about how to work around these limits using the stream application programming interface (API).The following set
XXX
methods take an additional input parameter other than the parameter index and the data item itself:
setAsciiStream(int paramIndex, InputStream istream, int length)
Takes the length of the stream, in bytes.
setBinaryStream(int paramIndex, InputStream istream, int length)
Takes the length of the stream, in bytes.
setCharacterStream(int paramIndex, Reader reader, int length)
Takes the length of the stream, in characters.
setUnicodeStream(int paramIndex, InputStream istream, int length)
Takes the length of the stream, in bytes.
The particular usefulness of the setCharacterStream
method is that when a very large Unicode value is input to a LONGVARCHAR
parameter, it can be more practical to send it through a java.io.Reader
object. JDBC will read the data from the stream as needed, until it reaches the end-of-file mark. The JDBC driver will do any necessary conversion from Unicode to the database character format.
Note:
The preceding stream methods can also be used for large objects (LOBs). Refer to "Reading and Writing BLOB and CLOB Data" for more information.Some of the other methods that take an additional parameter other than the parameter index and the data item itself are:
CHAR
data in the database is padded to the column width. This leads to a limitation in using the setCHAR
method to bind character data into the WHERE
clause of a SELECT
statement. The character data in the WHERE
clause must also be padded to the column width to produce a match in the SELECT
statement. This is especially troublesome if you do not know the column width.
To remedy this, Oracle has added the setFixedCHAR
method to the OraclePreparedStatement
class. This method runs a non-padded comparison.
Note:
Remember to cast your prepared statement object to OraclePreparedStatement
to use the setFixedCHAR
method.
There is no need to use setFixedCHAR
for an INSERT
statement. The database always automatically pads the data to the column width as it inserts it.
Example
The following example demonstrates the difference between the setCHAR
and setFixedCHAR
methods.
/* Schema is : create table my_table (col1 char(10)); insert into my_table values ('JDBC'); */ PreparedStatement pstmt = conn.prepareStatement ("select count(*) from my_table where col1 = ?"); pstmt.setString (1, "JDBC"); // Set the Bind Value runQuery (pstmt); // This will print " No of rows are 0" CHAR ch = new CHAR("JDBC ", null); ((OraclePreparedStatement)pstmt).setCHAR(1, ch); // Pad it to 10 bytes runQuery (pstmt); // This will print "No of rows are 1" ((OraclePreparedStatement)pstmt).setFixedCHAR(1, "JDBC"); runQuery (pstmt); // This will print "No of rows are 1" void runQuery (PreparedStatement ps) { // Run the Query ResultSet rs = pstmt.executeQuery (); while (rs.next()) System.out.println("No of rows are " + rs.getInt(1)); rs.close(); rs = null; }
The oracle.jdbc.OracleResultSetMetaData
interface is JDBC 2.0-compliant but does not implement the getSchemaName
and getTableName
methods because Oracle Database 10g does not make this feasible. Oracle does implement many methods to retrieve information about an Oracle result set, however.
Key methods include the following:
Returns the number of columns in an Oracle result set
String getColumnName(int column)
Returns the name of a specified column in an Oracle result set
Returns the SQL type of a specified column in an Oracle result set. If the column stores an Oracle object or collection, then this method returns OracleTypes.STRUCT
or OracleTypes.ARRAY
respectively.
String getColumnTypeName(int column)
Returns the SQL type name for a specified column of type REF
, STRUCT
, or ARRAY
. If the column stores an array or collection, then this method returns its SQL type name. If the column stores REF
data, then this method returns the SQL type name of the objects to which the object reference points.
The following example uses several of the methods in the OracleResultSetMetadata
interface to retrieve the number of columns from the EMP
table and the numerical type and SQL type name of each column:
DatabaseMetaData dbmd = conn.getMetaData(); ResultSet rset = dbmd.getTables("", "SCOTT", "EMP", null); while (rset.next()) { OracleResultSetMetaData orsmd = ((OracleResultSet)rset).getMetaData(); int numColumns = orsmd.getColumnCount(); System.out.println("Num of columns = " + numColumns); for (int i=0; i<numColumns; i++) { System.out.print ("Column Name=" + orsmd.getColumnName (i+1)); System.out.print (" Type=" + orsmd.getColumnType (i + 1) ); System.out.println (" Type Name=" + orsmd.getColumnTypeName (i + 1)); } }
The program returns the following output:
Num of columns = 5 Column Name=TABLE_CAT Type=12 Type Name=VARCHAR2 Column Name=TABLE_SCHEM Type=12 Type Name=VARCHAR2 Column Name=TABLE_NAME Type=12 Type Name=VARCHAR2 Column Name=TABLE_TYPE Type=12 Type Name=VARCHAR2 Column Name=TABLE_REMARKS Type=12 Type Name=VARCHAR2