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<span style="font-family:Helvetica,Arial; font-size:12pt; color:#000000"><b>UPDATE Command
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An UPDATE statement is used to directly change or modify the values stored in one or more fields in a specified record in a single table. 
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<b>Syntax
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</b></span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">UPDATE [ MEMORY ] <i>table_name</i> SET <i>column_name </i>= { <i>expression | query</i> } [, ...] [ WHERE <i>condition</i> ]
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or
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UPDATE [ MEMORY ] <i>table_name</i> SET <i>( column_names_list ) </i>= { <i>row_query</i> }  [ WHERE <i>condition</i> ]
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<b>Description
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</span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">UPDATE changes the values of the specified columns in all rows that satisfy the condition. Only the columns to be modified need be mentioned in the SET clause; columns not explicitly modified retain their previous values. 
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You can use sub-selects to modify a table using information contained in other tables in the database.</span><span style="font-family:Times New Roman; font-size:12pt; color:#000000"> </span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">
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MEMORY
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<table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="14"></td><td><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">If MEMORY keyword is specified before the <i>table_name</i> then an in-memory table is referenced, not a disk one.
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</span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><i>table_name</i>
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<table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="14"></td><td><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">The name of an existing table.
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</span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><i>column _name</i>
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<table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="14"></td><td><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">The name of a column in a table. 
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</span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><i>expression</i> 
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<table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="14"></td><td><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">An expression or a value to assign to a column. 
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</span></td></tr></table><table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="14"></td><td><span style="font-family:Helvetica,Arial; font-size:4pt; color:#000000"></span></td></tr></table><span style="font-family:Helvetica,Arial; font-size:4pt; color:#000000"></span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><i>query</i> 
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<table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="14"></td><td><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">A scalar query (SELECT statement) that supplies the single value to be assigned. Refer to the <a href=selectstatement.htm>SELECT</a> command for a description of the syntax. 
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</span></span></td></tr></table><table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="14"></td><td><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"></span></td></tr></table><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"></span><span style="font-family:Helvetica,Arial; font-size:4pt; color:#000000">
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</span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><i>condition </i>
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<table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="14"></td><td><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">An expression that returns a value of type boolean. Only rows for which this expression returns true will be updated. 
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</span></span></td></tr></table><table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="14"></td><td><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"></span></td></tr></table><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"></span><span style="font-family:Helvetica,Arial; font-size:4pt; color:#000000">
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</span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><i>column_names_list </i>
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<table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="14"></td><td><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">A list of a column names in a table. 
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</span></td></tr></table><table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="14"></td><td><span style="font-family:Helvetica,Arial; font-size:4pt; color:#000000"></span></td></tr></table><span style="font-family:Helvetica,Arial; font-size:4pt; color:#000000"></span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><i>row_query</i> 
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<table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="14"></td><td><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">A row query (SELECT statement) that supplies the single or multiple values to be assigned to the listed columns. Refer to the <a href=selectstatement.htm>SELECT</a> command for a description of the syntax. 
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</span></span></td></tr></table><table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="14"></td><td><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"></span></td></tr></table><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">
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<b>Examples:
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</b></span><span style="font-family:Helvetica,Arial; font-size:4pt; color:#000000"><b>
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</b><table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="14"></td><td><span style="font-family:Helvetica,Arial; font-size:4pt; color:#000000"></span></span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">UPDATE MyTable SET val2 = 'Many' WHERE val1 &gt; 2;
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</span></td></tr></table><table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="14"></td><td><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">UPDATE Events e SET Ticket_price = (SELECT Capacity FROM Venues WHERE VenueNo=e.VenueNo)*2 WHERE Ticket_price &lt;= 5
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</span></td></tr></table><table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="14"></td><td><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"></span></td></tr></table><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="12"></td><td><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">UPDATE Orders SET (ShipToAddr1,ShipToAddr2) = (SELECT Addr1, Addr2 FROM Customer WHERE CustNo=Orders.CustNo) WHERE CustNo IN (1221, 2156)</span></span><span style="font-family:Courier New; font-size:10pt; color:#000000">
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