Data Language, Datatypes,
CursorAdapter & XMLAdapter

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SQL
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MORE!
Enhanced sub-query support
Enhanced correlation support
Enhanced UNION support
Performance
Commands & Functions
Datatypes
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Remote Data
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CursorAdapter
XMLAdapter
SQL Pass-through (SPT)
OLEDB Provider
Enhancements

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Amount of JOINs and amount of subqueries in SQL statement. .
Amount of UNIONs in SQL SELECT statement.
Amount of tables referenced by SQL statement.
More than 24 items in IN list.
Multiple sub-query nesting.
* No hard coded limit!

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Sub-query in SELECT list (projection).
Sub-query in FROM clause (derived).
Sub-query in UPDATE SET list.
ORDER BY in conjunction with TOP N inside of non-correlated sub-query
Support for more complex expressions on the left side in comparison with sub-query

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Correlated UPDATE … FROM .
Correlated DELETE … FROM .
GROUP BY in correlated sub-query
SELECT * ;
FROM foo1 T1 ;
WHERE f1 IN (SELECT MAX(f1);
FROM foo2 T2 ;
WHERE T2.f2 = T1.f2;
GROUP BY f3)

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UNION in INSERT INTO ... SELECT ...
FROM ...
ORDER BY <field name> when using
UNION
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Referenced fields must be present in SELECT list for the last SELECT in the UNION.

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TOP N performance improvement
MIN()/MAX() optimization
Rushmore optimization changes
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LIKE
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INDEX ON DELETED() / NOT DELETED()
INDEX ON…FOR DELETED() / NOT DELETED()

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INDEX ON !DELETED() will be used to optimize
!DELETED() or DELETED() conditions when
INDEX ON DELETED() is not present.
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INDEX ON <…> FOR !DELETED() will be used to optimize !DELETED() or DELETED() when neither INDEX ON DELETED() or INDEX ON
!DELETED() is present.

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When ever it is possible to determine that a
Query should filter on DELETED() or !DELETED() a filtered index FOR DELETED() or FOR
!DELETED() will be used accordingly if no nonfiltered index exists.
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If only indexes filtered FOR !DELETED() were used for Rushmore optimization and SET
DELETED is ON, additional !DELETED() optimization is not done as it is unnecessary.

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BINARY index type …
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SET REFRESH changes
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CursorSetProp("Refresh") .
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SYS(1104,[cAlias | nWorkarea])
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FLUSH [{ IN<nWorkArea>|<cTableAlias>}|<cFileSpec>] [ FORCE ]
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SYS(3092) output to a file
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SET SQLBUFFERING / SELECT … WITH (Buffering = <lexpr>)
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CAST()
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ICASE()

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Similar to char data type except filled value is not padded (or trimmed) with spaces if value is assigned explicitly or by means of default value.
Fields from external sources that do not fit into
Varchar limits will map to Memo.
VarChar has priority over Character
Index has same structure as Character
Uses:
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Reduce size of indexes
With SQL Server VarChar (when < 254 bytes)

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Similar to VarChar except used to store binary data.
NO CPTRANS
Uses:
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TimeStamp (native)
GUID
Map to VarBinary in SQL Server

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Similar to Memo data type except it’s treated as a true binary data type.
NO CPTRANS
MODI MEMO displays HEX dump
SCATTER/GATHER MEMO
Uses:
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Image.PictureVal (Goodbye General!)
Map to BLOB in SQL Server

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SET COLLATE TO MACHINE
SET EXACT OFF
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SET COLLATE TO GENERAL
SET EXACT OFF expression C=C Q=C C=Q Q=Q
--------------- --- --- --- ---
"abc" = "abc" .T. .T. .T. .T.
"abc " = "abc" .T. .T. .T. .T.
"abc" = "abc " .F. .F. .F. .F.
"abc" = "ABC" .F. .F. .F. .F.
"ABC" = "abc" .F. .F. .F. .F.
expression C=C Q=C C=Q Q=Q
--------------- --- --- --- ---
"abc" = "abc" .T. .T. .T. .T.
"abc " = "abc" .T. .T. .T. .T.
"abc" = "abc " .F. .F. .F. .F.
"abc" = "ABC" .T. .F. .T. .F.
"ABC" = "abc" .T. .F. .T. .F.
SET COLLATE TO MACHINE
SET EXACT ON expression C=C Q=C C=Q Q=Q
--------------- --- --- --- ---
"abc" = "abc" .T. .T. .T. .T.
"abc " = "abc" .T. .F. .T. .F.
"abc" = "abc " .T. .F. .T. .F.
"abc" = "ABC" .F. .F. .F. .F.
"ABC" = "abc" .F. .F. .F. .F.
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Comparison rules
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SET COLLATE TO GENERAL
SET EXACT ON expression C=C Q=C C=Q Q=Q
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"abc" = "abc" .T. .T. .T. .T.
"abc " = "abc" .T. .F. .T. .F.
"abc" = "abc " .T. .F. .T. .F.
"abc" = "ABC" .T. .F. .T. .F.
"ABC" = "abc" .T. .F. .T. .F.
Type on Left Padding Case Sensitive
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Binary CHR(0) Always
Character CHR(32) SET COLLATE dependent

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DisconnectRollback
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Determines whether pending transaction has to be rolled back when connection is being disconnected. default (.F.)
RecordsFetched
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Returns amount of records currently fetched from the back end for ODBC/ADO based cursor.
FetchIsComplete
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Returns .T. if fetch process for the ODBC/ADO based cursor is complete.

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Ability to determine amount of records affected by an SPT execution.
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Via additional parameter for SQLEXEC and
SQLMORERESULTS functions:
 aCountInfo – Provides name of the array to populate with row count information. Array contains two columns: 1 –
Alias , 2 – Count .
SQLIDLEDISCONNECT function
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Similar behavior to implicit disconnect based on
IdleTimeOut property, now it can be done explicitly.
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The function fails if statement handle is busy or connection is in manual commit mode.

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Return Rowset from a stored procedure.
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SetResultSet / GetResultSet / ClearResultSet
When used in native VFP, return value is the alias of the returned rowset.

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Support for TIMESTAMP fields
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TimestampFieldList
Auto-refresh support
On demand record refresh
 ca.RecordRefresh([nRecords],[nRecordOffset])
Delayed Memo fetch
DEFAULT and CHECK constraints
MapVarChar / MapBinary

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Support for hierarchical XML
Support for XPath expressions.
XML encoding/decoding enhancements

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Taming Visual FoxPro‘s SQL
Real World Data Solutions For VFP
Tamar E. Granor with Della Martin
Hentzenwerke Publishing
Special offer 20 EURO for mass order but only if you are interested…