org.objectweb.cjdbc.common.sql
Class DeleteRequest

java.lang.Object
  extended byorg.objectweb.cjdbc.common.sql.AbstractRequest
      extended byorg.objectweb.cjdbc.common.sql.AbstractWriteRequest
          extended byorg.objectweb.cjdbc.common.sql.DeleteRequest
All Implemented Interfaces:
java.io.Serializable

public class DeleteRequest
extends AbstractWriteRequest
implements java.io.Serializable

An DeleteRequest is an SQL request with the following syntax:

DELETE [table1] FROM table1,table2,table3,... WHERE search-condition
 or DELETE t WHERE search-condition
 
Note that DELETE from multiple tables are not supported but this is not part of the SQL standard.

Version:
1.0
Author:
Emmanuel Cecchet , Julie Marguerite , Mathieu Peltier , Sara Bouchenak
See Also:
Serialized Form

Field Summary
private  java.util.ArrayList from
          ArrayList of String objects
private  boolean isUnique
          true if this query only deletes a single row.
private static long serialVersionUID
           
protected  java.util.ArrayList whereValues
          ArrayList of values String associated with the unique columns involved in this delete query.
 
Fields inherited from class org.objectweb.cjdbc.common.sql.AbstractWriteRequest
blocking, columns, pkValue, tableName
 
Fields inherited from class org.objectweb.cjdbc.common.sql.AbstractRequest
cacheable, cursorName, escapeProcessing, fetchSize, id, isAutoCommit, isParsed, isReadOnly, login, maxRows, requestType, sqlQuery, sqlSkeleton, timeoutInSeconds, transactionId, transactionIsolation
 
Constructor Summary
DeleteRequest(CJDBCInputStream in)
           
DeleteRequest(java.lang.String sqlQuery, boolean escapeProcessing, int timeout, java.lang.String lineSeparator)
          Creates a new DeleteRequest instance.
DeleteRequest(java.lang.String sqlQuery, boolean escapeProcessing, int timeout, java.lang.String lineSeparator, DatabaseSchema schema, int granularity, boolean isCaseSensitive)
          Creates a new DeleteRequest instance.
 
Method Summary
 void cloneParsing(AbstractRequest request)
          Clones the parsing of a request.
 void debug()
          Displays some debugging information about this request.
private  java.util.ArrayList getFromTables(java.lang.String fromClause, DatabaseSchema dbs)
          Extracts the tables from the given FROM clause and retrieves their alias if any.
 java.util.ArrayList getValues()
          Returns an ArrayList of String objects representing the values associated with the unique columns involved in this request.
private  java.util.ArrayList getWhereColumns(java.lang.String whereClause, java.util.ArrayList aliasedFrom)
          Gets all the columns involved in the given WHERE clause.
 boolean isUnique()
          Returns true if this query only deletes a single row.
 boolean needsMacroProcessing()
          Returns true if this request requires macro (RAND(), NOW(), ...) processing.
 void parse(DatabaseSchema schema, int granularity, boolean isCaseSensitive)
          Parses the SQL request and extracts the selected columns and tables given the DatabaseSchema of the database targeted by this request.
 boolean returnsResultSet()
          Does this request returns a ResultSet?
 
Methods inherited from class org.objectweb.cjdbc.common.sql.AbstractWriteRequest
cloneTableNameAndColumns, getColumns, getPk, getTableName, mightBlock, setBlocking
 
Methods inherited from class org.objectweb.cjdbc.common.sql.AbstractRequest
equals, getCacheAbility, getCursorName, getEscapeProcessing, getFetchSize, getId, getLineSeparator, getLogin, getMaxRows, getSQL, getSQLShortForm, getSqlSkeleton, getTimeout, getTransactionId, getTransactionIsolation, isAlter, isAutoCommit, isCreate, isDDL, isDelete, isDML, isDriverProcessed, isDrop, isInsert, isParsed, isReadOnly, isSelect, isUpdate, receiveResultSetParams, sendResultSetParams, sendToStream, setCacheAbility, setCursorName, setDriverProcessed, setFetchSize, setId, setIsAutoCommit, setIsReadOnly, setLogin, setMaxRows, setSQL, setSqlSkeleton, setTimeout, setTransactionId, setTransactionIsolation, trimCarriageReturnAndTabs
 
Methods inherited from class java.lang.Object
clone, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

serialVersionUID

private static final long serialVersionUID
See Also:
Constant Field Values

isUnique

private transient boolean isUnique
true if this query only deletes a single row.


from

private transient java.util.ArrayList from
ArrayList of String objects


whereValues

protected java.util.ArrayList whereValues
ArrayList of values String associated with the unique columns involved in this delete query.

The values instance variable is only used when a COLUMN_UNIQUE_DELETE granularity is applied. Here, the DELETE request is UNIQUE: all columns of the WHERE clause are UNIQUE and used in the left part of an equality. When such a granularity is used, the columns instance variable contains only UNIQUE columns.

See Also:
CachingGranularities
Constructor Detail

DeleteRequest

public DeleteRequest(java.lang.String sqlQuery,
                     boolean escapeProcessing,
                     int timeout,
                     java.lang.String lineSeparator,
                     DatabaseSchema schema,
                     int granularity,
                     boolean isCaseSensitive)
              throws java.sql.SQLException
Creates a new DeleteRequest instance. The caller must give an SQL request, without any leading or trailing spaces and beginning with 'delete ' (it will not be checked).

If the syntax is incorrect an exception is thrown.

Parameters:
sqlQuery - the SQL request
escapeProcessing - should the driver to escape processing before sending to the database ?
timeout - an int value
lineSeparator - the line separator used in the query
schema - a DatabaseSchema value
granularity - parsing granularity as defined in ParsingGranularities
isCaseSensitive - true if parsing is case sensitive
Throws:
java.sql.SQLException - if an error occurs

DeleteRequest

public DeleteRequest(java.lang.String sqlQuery,
                     boolean escapeProcessing,
                     int timeout,
                     java.lang.String lineSeparator)
Creates a new DeleteRequest instance. The caller must give an SQL request, without any leading or trailing spaces and beginning with 'delete ' (it will not be checked).

The request is not parsed but it can be done later by a call to parse(DatabaseSchema, int, boolean).

Parameters:
sqlQuery - the SQL request
escapeProcessing - should the driver to escape processing before sending to the database ?
timeout - an int value
lineSeparator - the line separator used in the query
See Also:
parse(org.objectweb.cjdbc.common.sql.schema.DatabaseSchema, int, boolean)

DeleteRequest

public DeleteRequest(CJDBCInputStream in)
              throws java.io.IOException
See Also:
AbstractWriteRequest
Method Detail

parse

public void parse(DatabaseSchema schema,
                  int granularity,
                  boolean isCaseSensitive)
           throws java.sql.SQLException
Parses the SQL request and extracts the selected columns and tables given the DatabaseSchema of the database targeted by this request.

An exception is thrown when the parsing fails. Warning, this method does not check the validity of the request. In particular, invalid request could be parsed without throwing an exception. However, valid SQL request should never throw an exception.

Specified by:
parse in class AbstractRequest
Parameters:
schema - a DatabaseSchema value
granularity - parsing granularity as defined in ParsingGranularities
isCaseSensitive - if parsing must be case sensitive
Throws:
java.sql.SQLException - if the parsing fails

cloneParsing

public void cloneParsing(AbstractRequest request)
Description copied from class: AbstractRequest
Clones the parsing of a request.

Specified by:
cloneParsing in class AbstractRequest
Parameters:
request - the parsed request to clone
See Also:
AbstractRequest.cloneParsing(AbstractRequest)

getFromTables

private java.util.ArrayList getFromTables(java.lang.String fromClause,
                                          DatabaseSchema dbs)
                                   throws java.sql.SQLException
Extracts the tables from the given FROM clause and retrieves their alias if any.

Parameters:
fromClause - the FROM clause of the request (without the FROM keyword)
dbs - the DatabaseSchema this request refers to
Returns:
an ArrayList of AliasedDatabaseTable objects
Throws:
an - SQLException if an error occurs
java.sql.SQLException

getWhereColumns

private java.util.ArrayList getWhereColumns(java.lang.String whereClause,
                                            java.util.ArrayList aliasedFrom)
Gets all the columns involved in the given WHERE clause.

The selected columns or tables must be found in the given ArrayList of AliasedDatabaseTable representing the FROM clause of the same request.

Parameters:
whereClause - WHERE clause of the request (without the WHERE keyword)
aliasedFrom - an ArrayList of AliasedDatabaseTable
Returns:
an ArrayList of TableColumn

getValues

public java.util.ArrayList getValues()
Returns an ArrayList of String objects representing the values associated with the unique columns involved in this request.

Returns:
an ArrayList value

isUnique

public boolean isUnique()
Returns true if this query only deletes a single row.

Returns:
a boolean value

needsMacroProcessing

public boolean needsMacroProcessing()
Description copied from class: AbstractRequest
Returns true if this request requires macro (RAND(), NOW(), ...) processing.

Specified by:
needsMacroProcessing in class AbstractRequest
Returns:
true if macro processing is required
See Also:
AbstractRequest.needsMacroProcessing()

returnsResultSet

public boolean returnsResultSet()
Description copied from class: AbstractRequest
Does this request returns a ResultSet?

Specified by:
returnsResultSet in class AbstractRequest
Returns:
true is this request will return a ResultSet
See Also:
AbstractRequest.returnsResultSet()

debug

public void debug()
Displays some debugging information about this request.

Overrides:
debug in class AbstractRequest


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