com.aspc.commander.sql

Class SelectCommand

java.lang.Object

com.aspc.commander.Command

com.aspc.commander.sql.SQLCommand

com.aspc.commander.sql.SelectCommand

All Implemented Interfaces:

CommandBuildResultsPlugin, ResultsEstimatePlugin

public class SelectCommand
extends SQLCommand
implements ResultsEstimatePlugin

Alows selection from any database class.
Syntax

  SELECT [DISTINCT] column[,...]
  FROM table
  [INNER JOIN inner_join]
  [CROSS JOIN cross_join]
  [LEFT [OUTER] JOIN left_join]
  [WHERE criteria]
  [ROW_IS row_is_id]
  [GROUP BY group_by_column[,...]]
  [ORDER BY order]
  [ARCHIVE archive_dt]
  [TRANSACTION [BEFORE] trans_id]
  

Usage

  /* Will fetch the fields from person */
  SELECT oi_shipping,avg(oi_value), max(oi_units)
  FROM Order_Items
  GROUP BY oi_shipping;

  /* Will fetch all fields from person */
  SELECT * FROM Person

  /* Will fetch all files in a folder called 'web' */
  SELECT name, size
  FROM DBFile
  WHERE folderId.name like 'web%'

  /* Will fetch all fields for a particular person */
  SELECT * FROM Person ROW_IS 92934234423
  

THREAD MODE: SINGLE THREADED command

Since:

3 December 2003

Author:

Nigel Leck

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	COL_CLASS_GID Column type Class GID
static java.lang.String	COL_CLASS_NAME Column type Class name
static java.lang.String	COL_GLOBAL_KEY Column type Global Key
static java.lang.String	COL_ROW_UID Column type Row UID
static java.lang.String	COL_XML_DATA Column type XML data
static java.lang.String	KEY_WORD_DISTINCT create a distinct set of values
static java.lang.String	KEY_WORD_GROUP group the result by a set of columns
static java.lang.String	PARAM_DISPLAY The PARAMETER DISPLAY
static java.lang.String	VARIABLE_CRITERIA the criteria variable
static java.lang.String	VARIABLE_ROW_IS the ROW_IS variable

Fields inherited from class com.aspc.commander.sql.SQLCommand

CURSOR_SIZE

Constructor Summary

Constructors

Constructor and Description
SelectCommand(Connection connection, Pattern pattern) std.

Method Summary

Modifier and Type	Method and Description
static void	disableHint(boolean flag) disable the hint logic
protected void	execute(Parser p) execute the command.
java.lang.String	getColumnName(int col) the column name
java.lang.String	getColumnType(int col) Gets the column type for the given column index, starting at one
long	getEstimatedRecordCount() The estimate record count
java.lang.String	getRecordID(int row) the record ID
java.lang.Object	getValue(int row, int col) the value for this row, column
boolean	hasFunctionAndNoGroupBy() Return whether the command contains function but no group by
static java.lang.String	parseCondition(java.lang.String condition, java.util.HashMap<java.lang.String,java.lang.String> alias) parse the condition
static java.lang.String	parseCrossJoin(VirtualDB layer, java.lang.String table, java.lang.String join, java.lang.String conditions, java.util.HashMap<java.lang.String,java.lang.String> alias) Note: the below is actually a left join parse the cross join
static void	parseJoin(boolean leftJoin, DBClassConcrete baseClass, java.lang.String join, java.util.HashMap alias) parse the join

Methods inherited from class com.aspc.commander.sql.SQLCommand

appendResult, appendResult, getCursorName, getRecordKey, isExecuteOnly

Methods inherited from class com.aspc.commander.Command

execute, extMakeThreadName, getConnection, getPattern, getRawTitle, getTitle, makeThreadName, recordCall, setTitle

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.aspc.commander.sql.results.CommandBuildResultsPlugin

getRawTitle

Field Detail

PARAM_DISPLAY

public static final java.lang.String PARAM_DISPLAY

The PARAMETER DISPLAY

See Also:

Constant Field Values

COL_ROW_UID

public static final java.lang.String COL_ROW_UID

Column type Row UID

See Also:

Constant Field Values

COL_GLOBAL_KEY

public static final java.lang.String COL_GLOBAL_KEY

Column type Global Key

See Also:

Constant Field Values

COL_CLASS_GID

public static final java.lang.String COL_CLASS_GID

Column type Class GID

See Also:

Constant Field Values

COL_CLASS_NAME

public static final java.lang.String COL_CLASS_NAME

Column type Class name

See Also:

Constant Field Values

COL_XML_DATA

public static final java.lang.String COL_XML_DATA

Column type XML data

See Also:

Constant Field Values

KEY_WORD_GROUP

public static final java.lang.String KEY_WORD_GROUP

group the result by a set of columns

See Also:

Constant Field Values

KEY_WORD_DISTINCT

public static final java.lang.String KEY_WORD_DISTINCT

create a distinct set of values

See Also:

Constant Field Values

VARIABLE_CRITERIA

public static final java.lang.String VARIABLE_CRITERIA

the criteria variable

See Also:

Constant Field Values

VARIABLE_ROW_IS

public static final java.lang.String VARIABLE_ROW_IS

the ROW_IS variable

See Also:

Constant Field Values

Constructor Detail

SelectCommand

public SelectCommand(Connection connection,
                     Pattern pattern)

std. Command.

Parameters:

connection - the connection

pattern - the pattern

Method Detail

disableHint

public static void disableHint(boolean flag)

disable the hint logic

Parameters:

flag - true to disable.

execute

protected void execute(@Nonnull
                       Parser p)
                throws java.lang.Exception

execute the command.

Specified by:

execute in class Command

Parameters:

p - The parser

Throws:

java.lang.Exception - A serious problem

parseJoin

public static void parseJoin(boolean leftJoin,
                             DBClassConcrete baseClass,
                             java.lang.String join,
                             java.util.HashMap alias)
                      throws java.sql.SQLException

parse the join

     tags tag2_ on this_.tag_id=tag2_.id


 left outer join wcm_content children2_ on this_.id=children2_.parent_id\
 

http://en.wikipedia.org/wiki/Join_(SQL)#Inner_join

Parameters:

leftJoin - is left join

baseClass - The base class

join - the condition

alias - the alias

Throws:

java.sql.SQLException - can't handle more than simple links.

parseCrossJoin

public static java.lang.String parseCrossJoin(VirtualDB layer,
                                              java.lang.String table,
                                              java.lang.String join,
                                              java.lang.String conditions,
                                              java.util.HashMap<java.lang.String,java.lang.String> alias)
                                       throws java.lang.Exception

Note: the below is actually a left join parse the cross join

    SELECT id
    FROM wcm_content wcmblogent0_
         cross join wcm_status wcmstatus1_
    WHERE wcmblogent0_.class='org.weceem.blog.WcmBlogEntry'
      AND wcmblogent0_.status_id=wcmstatus1_.id
      AND wcmblogent0_.parent_id=1
      AND wcmstatus1_.public_content=1
 

http://en.wikipedia.org/wiki/Join_(SQL)#Cross_join

Parameters:

layer - the layer

table - the base class

join - the condition

conditions - the conditions

alias - the alias

Returns:

new condition

Throws:

java.lang.Exception - can't handle more than simple links.

parseCondition

public static java.lang.String parseCondition(@Nonnull
                                              java.lang.String condition,
                                              java.util.HashMap<java.lang.String,java.lang.String> alias)

parse the condition

Parameters:

condition - the condition

alias - the alias

Returns:

the beautified version

hasFunctionAndNoGroupBy

public boolean hasFunctionAndNoGroupBy()

Return whether the command contains function but no group by

Returns:

true if it has a function.

getColumnName

public java.lang.String getColumnName(int col)

the column name

Specified by:

getColumnName in interface CommandBuildResultsPlugin

Parameters:

col - the column

Returns:

the name

getColumnType

public java.lang.String getColumnType(int col)
                               throws java.lang.Exception

Gets the column type for the given column index, starting at one

Specified by:

getColumnType in interface CommandBuildResultsPlugin

Parameters:

col - the column index

Returns:

String the column type

Throws:

java.lang.Exception - a serious problem

getRecordID

public java.lang.String getRecordID(int row)

the record ID

Specified by:

getRecordID in interface CommandBuildResultsPlugin

Parameters:

row - the row index

Returns:

the record ID

getValue

public java.lang.Object getValue(int row,
                                 int col)
                          throws java.lang.Exception

the value for this row, column

Specified by:

getValue in interface CommandBuildResultsPlugin

Parameters:

row - the row index

col - the column

Returns:

Object the value for the given row and column

Throws:

java.lang.Exception - a serious problem

getEstimatedRecordCount

public long getEstimatedRecordCount()

Description copied from interface: ResultsEstimatePlugin

The estimate record count

Specified by:

getEstimatedRecordCount in interface ResultsEstimatePlugin

Returns:

the estimated record count