ResultSetMetaData
public
interface
ResultSetMetaData
implements
Wrapper
| java.sql.ResultSetMetaData
|
 Known Indirect Subclasses
| RowSetMetaData |
An object that contains information about the columns in a
RowSet object.
|
|
An object that can be used to get information about the types
and properties of the columns in a ResultSet object.
The following code fragment creates the ResultSet object rs,
creates the ResultSetMetaData object rsmd, and uses rsmd
to find out how many columns rs has and whether the first column in rs
can be used in a WHERE clause.
ResultSet rs = stmt.executeQuery("SELECT a, b, c FROM TABLE2");
ResultSetMetaData rsmd = rs.getMetaData();
int numberOfColumns = rsmd.getColumnCount();
boolean b = rsmd.isSearchable(1);
Summary
Constants |
|---|
int |
columnNoNulls
The constant indicating that a
column does not allow NULL values.
|
int |
columnNullable
The constant indicating that a
column allows NULL values.
|
int |
columnNullableUnknown
The constant indicating that the
nullability of a column's values is unknown.
|
Public methods |
|---|
abstract
String
|
getCatalogName(int column)
Gets the designated column's table's catalog name.
|
abstract
String
|
getColumnClassName(int column)
Returns the fully-qualified name of the Java class whose instances
are manufactured if the method ResultSet.getObject
is called to retrieve a value
from the column.
|
abstract
int
|
getColumnCount()
Returns the number of columns in this ResultSet object.
|
abstract
int
|
getColumnDisplaySize(int column)
Indicates the designated column's normal maximum width in characters.
|
abstract
String
|
getColumnLabel(int column)
Gets the designated column's suggested title for use in printouts and
displays.
|
abstract
String
|
getColumnName(int column)
Get the designated column's name.
|
abstract
int
|
getColumnType(int column)
Retrieves the designated column's SQL type.
|
abstract
String
|
getColumnTypeName(int column)
Retrieves the designated column's database-specific type name.
|
abstract
int
|
getPrecision(int column)
Get the designated column's specified column size.
|
abstract
int
|
getScale(int column)
Gets the designated column's number of digits to right of the decimal point.
|
abstract
String
|
getSchemaName(int column)
Get the designated column's table's schema.
|
abstract
String
|
getTableName(int column)
Gets the designated column's table name.
|
abstract
boolean
|
isAutoIncrement(int column)
Indicates whether the designated column is automatically numbered.
|
abstract
boolean
|
isCaseSensitive(int column)
Indicates whether a column's case matters.
|
abstract
boolean
|
isCurrency(int column)
Indicates whether the designated column is a cash value.
|
abstract
boolean
|
isDefinitelyWritable(int column)
Indicates whether a write on the designated column will definitely succeed.
|
abstract
int
|
isNullable(int column)
Indicates the nullability of values in the designated column.
|
abstract
boolean
|
isReadOnly(int column)
Indicates whether the designated column is definitely not writable.
|
abstract
boolean
|
isSearchable(int column)
Indicates whether the designated column can be used in a where clause.
|
abstract
boolean
|
isSigned(int column)
Indicates whether values in the designated column are signed numbers.
|
abstract
boolean
|
isWritable(int column)
Indicates whether it is possible for a write on the designated column to succeed.
|
Inherited methods |
|---|
From
interface
java.sql.Wrapper
abstract
boolean
|
isWrapperFor(Class<?> iface)
Returns true if this either implements the interface argument or is directly or indirectly a wrapper
for an object that does.
|
abstract
<T>
T
|
unwrap(Class<T> iface)
Returns an object that implements the given interface to allow access to
non-standard methods, or standard methods not exposed by the proxy.
|
|
Constants
columnNoNulls
int columnNoNulls
The constant indicating that a
column does not allow NULL values.
Constant Value:
0
(0x00000000)
columnNullable
int columnNullable
The constant indicating that a
column allows NULL values.
Constant Value:
1
(0x00000001)
columnNullableUnknown
int columnNullableUnknown
The constant indicating that the
nullability of a column's values is unknown.
Constant Value:
2
(0x00000002)
Public methods
getCatalogName
String getCatalogName (int column)
Gets the designated column's table's catalog name.
| Parameters |
|---|
column |
int:
the first column is 1, the second is 2, ... |
| Returns |
|---|
String |
the name of the catalog for the table in which the given column
appears or "" if not applicable |
getColumnClassName
String getColumnClassName (int column)
Returns the fully-qualified name of the Java class whose instances
are manufactured if the method ResultSet.getObject
is called to retrieve a value
from the column. ResultSet.getObject may return a subclass of the
class returned by this method.
| Parameters |
|---|
column |
int:
the first column is 1, the second is 2, ... |
| Returns |
|---|
String |
the fully-qualified name of the class in the Java programming
language that would be used by the method
ResultSet.getObject to retrieve the value in the specified
column. This is the class name used for custom mapping. |
getColumnCount
int getColumnCount ()
Returns the number of columns in this ResultSet object.
| Returns |
|---|
int |
the number of columns |
getColumnDisplaySize
int getColumnDisplaySize (int column)
Indicates the designated column's normal maximum width in characters.
| Parameters |
|---|
column |
int:
the first column is 1, the second is 2, ... |
| Returns |
|---|
int |
the normal maximum number of characters allowed as the width
of the designated column |
getColumnLabel
String getColumnLabel (int column)
Gets the designated column's suggested title for use in printouts and
displays. The suggested title is usually specified by the SQL AS
clause. If a SQL AS is not specified, the value returned from
getColumnLabel will be the same as the value returned by the
getColumnName method.
| Parameters |
|---|
column |
int:
the first column is 1, the second is 2, ... |
| Returns |
|---|
String |
the suggested column title |
getColumnName
String getColumnName (int column)
Get the designated column's name.
| Parameters |
|---|
column |
int:
the first column is 1, the second is 2, ... |
getColumnType
int getColumnType (int column)
Retrieves the designated column's SQL type.
| Parameters |
|---|
column |
int:
the first column is 1, the second is 2, ... |
| Returns |
|---|
int |
SQL type from java.sql.Types |
getColumnTypeName
String getColumnTypeName (int column)
Retrieves the designated column's database-specific type name.
| Parameters |
|---|
column |
int:
the first column is 1, the second is 2, ... |
| Returns |
|---|
String |
type name used by the database. If the column type is
a user-defined type, then a fully-qualified type name is returned. |
getPrecision
int getPrecision (int column)
Get the designated column's specified column size.
For numeric data, this is the maximum precision. For character data, this is the length in characters.
For datetime datatypes, this is the length in characters of the String representation (assuming the
maximum allowed precision of the fractional seconds component). For binary data, this is the length in bytes. For the ROWID datatype,
this is the length in bytes. 0 is returned for data types where the
column size is not applicable.
| Parameters |
|---|
column |
int:
the first column is 1, the second is 2, ... |
getScale
int getScale (int column)
Gets the designated column's number of digits to right of the decimal point.
0 is returned for data types where the scale is not applicable.
| Parameters |
|---|
column |
int:
the first column is 1, the second is 2, ... |
getSchemaName
String getSchemaName (int column)
Get the designated column's table's schema.
| Parameters |
|---|
column |
int:
the first column is 1, the second is 2, ... |
| Returns |
|---|
String |
schema name or "" if not applicable |
getTableName
String getTableName (int column)
Gets the designated column's table name.
| Parameters |
|---|
column |
int:
the first column is 1, the second is 2, ... |
| Returns |
|---|
String |
table name or "" if not applicable |
isAutoIncrement
boolean isAutoIncrement (int column)
Indicates whether the designated column is automatically numbered.
| Parameters |
|---|
column |
int:
the first column is 1, the second is 2, ... |
| Returns |
|---|
boolean |
true if so; false otherwise |
isCaseSensitive
boolean isCaseSensitive (int column)
Indicates whether a column's case matters.
| Parameters |
|---|
column |
int:
the first column is 1, the second is 2, ... |
| Returns |
|---|
boolean |
true if so; false otherwise |
isCurrency
boolean isCurrency (int column)
Indicates whether the designated column is a cash value.
| Parameters |
|---|
column |
int:
the first column is 1, the second is 2, ... |
| Returns |
|---|
boolean |
true if so; false otherwise |
isDefinitelyWritable
boolean isDefinitelyWritable (int column)
Indicates whether a write on the designated column will definitely succeed.
| Parameters |
|---|
column |
int:
the first column is 1, the second is 2, ... |
| Returns |
|---|
boolean |
true if so; false otherwise |
isNullable
int isNullable (int column)
Indicates the nullability of values in the designated column.
| Parameters |
|---|
column |
int:
the first column is 1, the second is 2, ... |
| Returns |
|---|
int |
the nullability status of the given column; one of columnNoNulls,
columnNullable or columnNullableUnknown |
isReadOnly
boolean isReadOnly (int column)
Indicates whether the designated column is definitely not writable.
| Parameters |
|---|
column |
int:
the first column is 1, the second is 2, ... |
| Returns |
|---|
boolean |
true if so; false otherwise |
isSearchable
boolean isSearchable (int column)
Indicates whether the designated column can be used in a where clause.
| Parameters |
|---|
column |
int:
the first column is 1, the second is 2, ... |
| Returns |
|---|
boolean |
true if so; false otherwise |
isSigned
boolean isSigned (int column)
Indicates whether values in the designated column are signed numbers.
| Parameters |
|---|
column |
int:
the first column is 1, the second is 2, ... |
| Returns |
|---|
boolean |
true if so; false otherwise |
isWritable
boolean isWritable (int column)
Indicates whether it is possible for a write on the designated column to succeed.
| Parameters |
|---|
column |
int:
the first column is 1, the second is 2, ... |
| Returns |
|---|
boolean |
true if so; false otherwise |
Developers