Module java.sql
Package java.sql

Interface ResultSetMetaData

All Superinterfaces:
Wrapper
All Known Subinterfaces:
RowSetMetaData
All Known Implementing Classes:
RowSetMetaDataImpl

public interface ResultSetMetaData extends Wrapper
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);

 
Since:
1.1
  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final int
    The constant indicating that a column does not allow NULL values.
    static final int
    The constant indicating that a column allows NULL values.
    static final int
    The constant indicating that the nullability of a column's values is unknown.
  • Method Summary

    Modifier and Type
    Method
    Description
    getCatalogName​(int column)
    Gets the designated column's table's catalog name.
    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.
    int
    Returns the number of columns in this ResultSet object.
    int
    getColumnDisplaySize​(int column)
    Indicates the designated column's normal maximum width in characters.
    getColumnLabel​(int column)
    Gets the designated column's suggested title for use in printouts and displays.
    getColumnName​(int column)
    Get the designated column's name.
    int
    getColumnType​(int column)
    Retrieves the designated column's SQL type.
    getColumnTypeName​(int column)
    Retrieves the designated column's database-specific type name.
    int
    getPrecision​(int column)
    Get the designated column's specified column size.
    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.
    getSchemaName​(int column)
    Get the designated column's table's schema.
    getTableName​(int column)
    Gets the designated column's table name.
    boolean
    isAutoIncrement​(int column)
    Indicates whether the designated column is automatically numbered.
    boolean
    isCaseSensitive​(int column)
    Indicates whether a column's case matters.
    boolean
    isCurrency​(int column)
    Indicates whether the designated column is a cash value.
    boolean
    isDefinitelyWritable​(int column)
    Indicates whether a write on the designated column will definitely succeed.
    int
    isNullable​(int column)
    Indicates the nullability of values in the designated column.
    boolean
    isReadOnly​(int column)
    Indicates whether the designated column is definitely not writable.
    boolean
    isSearchable​(int column)
    Indicates whether the designated column can be used in a where clause.
    boolean
    isSigned​(int column)
    Indicates whether values in the designated column are signed numbers.
    boolean
    isWritable​(int column)
    Indicates whether it is possible for a write on the designated column to succeed.

    Methods declared in interface java.sql.Wrapper

    isWrapperFor, unwrap
  • Field Details

    • columnNoNulls

      static final int columnNoNulls
      The constant indicating that a column does not allow NULL values.
      See Also:
      Constant Field Values
    • columnNullable

      static final int columnNullable
      The constant indicating that a column allows NULL values.
      See Also:
      Constant Field Values
    • columnNullableUnknown

      static final int columnNullableUnknown
      The constant indicating that the nullability of a column's values is unknown.
      See Also:
      Constant Field Values
  • Method Details

    • getColumnCount

      int getColumnCount() throws SQLException
      Returns the number of columns in this ResultSet object.
      Returns:
      the number of columns
      Throws:
      SQLException - if a database access error occurs
    • isAutoIncrement

      boolean isAutoIncrement(int column) throws SQLException
      Indicates whether the designated column is automatically numbered.
      Parameters:
      column - the first column is 1, the second is 2, ...
      Returns:
      true if so; false otherwise
      Throws:
      SQLException - if a database access error occurs
    • isCaseSensitive

      boolean isCaseSensitive(int column) throws SQLException
      Indicates whether a column's case matters.
      Parameters:
      column - the first column is 1, the second is 2, ...
      Returns:
      true if so; false otherwise
      Throws:
      SQLException - if a database access error occurs
    • isSearchable

      boolean isSearchable(int column) throws SQLException
      Indicates whether the designated column can be used in a where clause.
      Parameters:
      column - the first column is 1, the second is 2, ...
      Returns:
      true if so; false otherwise
      Throws:
      SQLException - if a database access error occurs
    • isCurrency

      boolean isCurrency(int column) throws SQLException
      Indicates whether the designated column is a cash value.
      Parameters:
      column - the first column is 1, the second is 2, ...
      Returns:
      true if so; false otherwise
      Throws:
      SQLException - if a database access error occurs
    • isNullable

      int isNullable(int column) throws SQLException
      Indicates the nullability of values in the designated column.
      Parameters:
      column - the first column is 1, the second is 2, ...
      Returns:
      the nullability status of the given column; one of columnNoNulls, columnNullable or columnNullableUnknown
      Throws:
      SQLException - if a database access error occurs
    • isSigned

      boolean isSigned(int column) throws SQLException
      Indicates whether values in the designated column are signed numbers.
      Parameters:
      column - the first column is 1, the second is 2, ...
      Returns:
      true if so; false otherwise
      Throws:
      SQLException - if a database access error occurs
    • getColumnDisplaySize

      int getColumnDisplaySize(int column) throws SQLException
      Indicates the designated column's normal maximum width in characters.
      Parameters:
      column - the first column is 1, the second is 2, ...
      Returns:
      the normal maximum number of characters allowed as the width of the designated column
      Throws:
      SQLException - if a database access error occurs
    • getColumnLabel

      String getColumnLabel(int column) throws SQLException
      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 - the first column is 1, the second is 2, ...
      Returns:
      the suggested column title
      Throws:
      SQLException - if a database access error occurs
    • getColumnName

      String getColumnName(int column) throws SQLException
      Get the designated column's name.
      Parameters:
      column - the first column is 1, the second is 2, ...
      Returns:
      column name
      Throws:
      SQLException - if a database access error occurs
    • getSchemaName

      String getSchemaName(int column) throws SQLException
      Get the designated column's table's schema.
      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
    • getPrecision

      int getPrecision(int column) throws SQLException
      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 - the first column is 1, the second is 2, ...
      Returns:
      precision
      Throws:
      SQLException - if a database access error occurs
    • getScale

      int getScale(int column) throws SQLException
      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 - the first column is 1, the second is 2, ...
      Returns:
      scale
      Throws:
      SQLException - if a database access error occurs
    • getTableName

      String getTableName(int column) throws SQLException
      Gets the designated column's table name.
      Parameters:
      column - the first column is 1, the second is 2, ...
      Returns:
      table name or "" if not applicable
      Throws:
      SQLException - if a database access error occurs
    • getCatalogName

      String getCatalogName(int column) throws SQLException
      Gets the designated column's table's catalog name.
      Parameters:
      column - the first column is 1, the second is 2, ...
      Returns:
      the name of the catalog for the table in which the given column appears or "" if not applicable
      Throws:
      SQLException - if a database access error occurs
    • getColumnType

      int getColumnType(int column) throws SQLException
      Retrieves the designated column's SQL type.
      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
      See Also:
      Types
    • getColumnTypeName

      String getColumnTypeName(int column) throws SQLException
      Retrieves the designated column's database-specific type name.
      Parameters:
      column - the first column is 1, the second is 2, ...
      Returns:
      type name used by the database. If the column type is a user-defined type, then a fully-qualified type name is returned.
      Throws:
      SQLException - if a database access error occurs
    • isReadOnly

      boolean isReadOnly(int column) throws SQLException
      Indicates whether the designated column is definitely not writable.
      Parameters:
      column - the first column is 1, the second is 2, ...
      Returns:
      true if so; false otherwise
      Throws:
      SQLException - if a database access error occurs
    • isWritable

      boolean isWritable(int column) throws SQLException
      Indicates whether it is possible for a write on the designated column to succeed.
      Parameters:
      column - the first column is 1, the second is 2, ...
      Returns:
      true if so; false otherwise
      Throws:
      SQLException - if a database access error occurs
    • isDefinitelyWritable

      boolean isDefinitelyWritable(int column) throws SQLException
      Indicates whether a write on the designated column will definitely succeed.
      Parameters:
      column - the first column is 1, the second is 2, ...
      Returns:
      true if so; false otherwise
      Throws:
      SQLException - if a database access error occurs
    • getColumnClassName

      String getColumnClassName(int column) throws SQLException

      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 - the first column is 1, the second is 2, ...
      Returns:
      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.
      Throws:
      SQLException - if a database access error occurs
      Since:
      1.2