interbase.interclient
Class ResultSetMetaData

java.lang.Object
  |
  +--interbase.interclient.ResultSetMetaData

public final class ResultSetMetaData

extends Object

implements ResultSetMetaData

Describes column information for a result set.

A ResultSetMetaData object can be used to find out about the types and properties of the columns in a ResultSet.

InterClient Notes:
Here are the column names, labels, and base tables to expect from some typical result sets:

Query	Column Name	Column Label	Table Name
select F from T	"F"	"F"	"T"
select F as A from T	"F"	"A"	"T"
select F+1 from T	""	""	""
select MAX(F) from T	"MAX"	"MAX"	""

Notice that calculated result columns have no physical table name, and may or may not have an ad hoc column label or name.

Since:

JDBC 1, with extended behavior in JDBC 2

Field Summary

static int	columnNoNulls Does not allow NULL values.
static int	columnNullable Allows NULL values.
static int	columnNullableUnknown Nullability unknown.

Fields inherited from interface java.sql.ResultSetMetaData

columnNoNulls, columnNullable, columnNullableUnknown

Method Summary

int	getArrayBaseType(int column) Gets an array column's base SQL type from java.sql.Types.
int[][]	getArrayDimensions(int column) Gets an array column's dimensions and bounds.
String	getCatalogName(int column) What's a column's table's catalog name.
String	getColumnClassName(int column) Return the fully qualified name of the Java class whose instances are manufactured if ResultSet.getObject() is called to retrieve a value from the column.
int	getColumnCount() Gets the number of columns in the ResultSet.
int	getColumnDisplaySize(int column) What's the column's normal max width in chars.
String	getColumnLabel(int column) Gets the suggested column title for use in printouts and displays.
String	getColumnName(int column) What's a column's name.
int	getColumnType(int column) What's a column's SQL type.
String	getColumnTypeName(int column) What's a column's data source specific type name.
int	getPrecision(int column) What's a column's number of decimal digits.
int	getScale(int column) What's a column's number of digits to right of the decimal point.
String	getSchemaName(int column) What's a column's table's schema.
String	getTableName(int column) Gets a column's origination table name.
boolean	isAutoIncrement(int column) Is the column automatically numbered, thus read-only.
boolean	isCaseSensitive(int column) Does a column's case matters.
boolean	isCurrency(int column) Is the column a cash value.
boolean	isDefinitelyWritable(int column) Will a write on the column definitely succeed.
int	isNullable(int column) Can you can put a NULL in this column.
boolean	isReadOnly(int column) Is a column definitely not writable.
boolean	isSearchable(int column) Can a column be used in a where clause.
boolean	isSigned(int column) Is the column a signed number.
boolean	isWritable(int column) Is it possible for a write on the column to succeed.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

columnNoNulls

public static final int columnNoNulls

Does not allow NULL values.

Since:

JDBC 1

columnNullable

public static final int columnNullable

Allows NULL values.

Since:

JDBC 1

columnNullableUnknown

public static final int columnNullableUnknown

Nullability unknown.

Since:

JDBC 1

Method Detail

getColumnCount

public int getColumnCount()
                   throws SQLException

Gets the number of columns in the ResultSet.

Specified by:

getColumnCount in interface ResultSetMetaData

Returns:

the number

Throws:

SQLException - if a database access error occurs

Since:

JDBC 1

isAutoIncrement

public boolean isAutoIncrement(int column)
                        throws SQLException

Is the column automatically numbered, thus read-only.

InterClient note: Always returns false for InterClient. The capability does not currently exist to determine an InterBase generator field dynamically.

Specified by:

isAutoIncrement in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

true if so

Throws:

SQLException - if a database access error occurs

Since:

JDBC 1, subject to further functional refinements

isCaseSensitive

public boolean isCaseSensitive(int column)
                        throws SQLException

Does a column's case matters.

InterClient note: Always returns true for InterBase. Text fields in InterBase are always case sensitive, even text blobs when using the 'containing' operator.

Specified by:

isCaseSensitive in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

true if so

Throws:

SQLException - if a database access error occurs

Since:

JDBC 1

isSearchable

public boolean isSearchable(int column)
                     throws SQLException

Can a column be used in a where clause.

InterClient note: Always returns true for InterBase. In InterBase, even a blob field can be used in a where clause, eg. "WHERE blob-field CONTAINING foobar"

Specified by:

isSearchable in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

true if so

Throws:

SQLException - if a database access error occurs

Since:

JDBC 1

isCurrency

public boolean isCurrency(int column)
                   throws SQLException

Is the column a cash value.

InterClient note: Always returns false for InterBase. InterBase does not support a money type.

Specified by:

isCurrency in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

true if so

Throws:

SQLException - if a database access error occurs

Since:

JDBC 1

isNullable

public int isNullable(int column)
               throws SQLException

Can you can put a NULL in this column.

InterClient note: Unlike other RDBMS vendors, InterBase can always determine column nullability dynamically, so InterClient never returns columnNullableUnknown.

Specified by:

isNullable in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

columnNoNulls, columnNullable or columnNullableUnknown

Throws:

SQLException - if a database access error occurs

Since:

JDBC 1

isSigned

public boolean isSigned(int column)
                 throws SQLException

Is the column a signed number.

Specified by:

isSigned in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

true if so

Throws:

SQLException - if a database access error occurs

Since:

JDBC 1

getColumnDisplaySize

public int getColumnDisplaySize(int column)
                         throws SQLException

What's the column's normal max width in chars.

Specified by:

getColumnDisplaySize in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

max width

Throws:

SQLException - if a database access error occurs

Since:

JDBC 1

getColumnLabel

public String getColumnLabel(int column)
                      throws SQLException

Gets the suggested column title for use in printouts and displays.

InterClient Notes:
See the table in the ResultSetMetaData class header documentation for the column labels associated with some typical SQL queries.

Specified by:

getColumnLabel in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

true if so

Throws:

SQLException - if a database access error occurs

Since:

JDBC 1

getColumnName

public String getColumnName(int column)
                     throws SQLException

What's a column's name.

InterClient Notes:
See the table in the ResultSetMetaData class header documentation for the column names associated with some typical SQL queries.

Specified by:

getColumnName in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

column name

Throws:

SQLException - if a database access error occurs

Since:

JDBC 1

getSchemaName

public String getSchemaName(int column)
                     throws SQLException

What's a column's table's schema.

InterClient note: Always returns "". InterBase does not support schemas.

Specified by:

getSchemaName in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

schema name or "" if not applicable

Throws:

SQLException - if a database access error occurs

Since:

JDBC 1, not supported

getPrecision

public int getPrecision(int column)
                 throws SQLException

What's a column's number of decimal digits.

Specified by:

getPrecision in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

precision

Throws:

SQLException - if a database access error occurs

Since:

JDBC 1

getScale

public int getScale(int column)
             throws SQLException

What's a column's number of digits to right of the decimal point.

Specified by:

getScale in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

scale

Throws:

SQLException - if a database access error occurs

Since:

JDBC 1

getTableName

public String getTableName(int column)
                    throws SQLException

Gets a column's origination table name.

InterClient Notes:
See the table in the ResultSetMetaData class header documentation for the tables names associated with some typical SQL queries.

Specified by:

getTableName in interface ResultSetMetaData

Returns:

table name or "" if not applicable

Throws:

SQLException - if a database access error occurs

Since:

JDBC 1

getCatalogName

public String getCatalogName(int column)
                      throws SQLException

What's a column's table's catalog name.

InterClient note: Always returns "". InterBase does not support catalogs.

Specified by:

getCatalogName in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

column name or "" if not applicable.

Throws:

SQLException - if a database access error occurs

Since:

JDBC 1, not supported

getColumnType

public int getColumnType(int column)
                  throws SQLException

What's a column's SQL type.

Specified by:

getColumnType in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

SQL type from java.sql.Types

Throws:

SQLException - if a database access error occurs

Since:

JDBC 1

getColumnTypeName

public String getColumnTypeName(int column)
                         throws SQLException

What's a column's data source specific type name.

Specified by:

getColumnTypeName in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

type name, if a UDT then a fully qualified type name is returned

Throws:

SQLException - if a database access error occurs

Since:

JDBC 1

isReadOnly

public boolean isReadOnly(int column)
                   throws SQLException

Is a column definitely not writable.

InterClient note: This returns true for a column which is a computed field, or is a view field, or the current user does not have the necessary SQL privileges to write to this field.

Specified by:

isReadOnly in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

true if so

Throws:

SQLException - if a database access error occurs

Since:

JDBC 1, behavior subject to further functional refinements

isWritable

public boolean isWritable(int column)
                   throws SQLException

Is it possible for a write on the column to succeed.

InterClient note: This returns true for a column which is not a computed field, and is not a view field, and the current user has the necessary SQL privileges to write to this field.

Specified by:

isWritable in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

true if so

Throws:

SQLException - if a database access error occurs

Since:

JDBC 1, behavior subject to further functional refinements

isDefinitelyWritable

public boolean isDefinitelyWritable(int column)
                             throws SQLException

Will a write on the column definitely succeed.

InterClient note: Always returns false. We can never guarantee this for InterBase because there may be triggers which could abort upon writing the column.

Specified by:

isDefinitelyWritable in interface ResultSetMetaData

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

true if so

Throws:

SQLException - if a database access error occurs

Since:

JDBC 1, behavior subject to further functional refinements

getColumnClassName

public String getColumnClassName(int column)
                          throws SQLException

Return the fully qualified name of the Java class whose instances are manufactured if ResultSet.getObject() is called to retrieve a value from the column. ResultSet.getObject() may return a subClass of the class returned by this method.

Specified by:

getColumnClassName in interface ResultSetMetaData

Throws:

SQLException - if a database access error occurs

Since:

JDBC 2, not supported

getArrayBaseType

public int getArrayBaseType(int column)
                     throws SQLException

Gets an array column's base SQL type from java.sql.Types. The result column must be of type java.sql.Types.ARRAY.

Parameters:

column - the first column is 1, the second is 2, ...

Throws:

SQLException - if a database access error occurs

Since:

Extension, proposed for InterClient 3.0

getArrayDimensions

public int[][] getArrayDimensions(int column)
                           throws SQLException

Gets an array column's dimensions and bounds. The result column must be of type java.sql.Types.ARRAY.

Parameters:

column - the first column is 1, the second is 2, ...

Returns:

an array of arrays describing dimensions and bounds for each dimension.

Throws:

SQLException - if a database access error occurs

Since:

Extension, proposed for InterClient 3.0