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<span style="font-family:Helvetica,Arial; font-size:12pt; color:#000000"><b>CREATE INDEX Command
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CREATE INDEX defines a new index on an existing table. 
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<b>Syntax
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</b></span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><span style="font-family:Helvetica,Arial; font-size:10pt; color:#010100">CREATE [ UNIQUE ] INDEX </span></span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><span style="font-family:Helvetica,Arial; font-size:10pt; color:#010100"><i>index_name</i></span></span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><span style="font-family:Helvetica,Arial; font-size:10pt; color:#010100"> ON [ MEMORY ] </span></span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><span style="font-family:Helvetica,Arial; font-size:10pt; color:#010100"><i>table_name</i></span></span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><span style="font-family:Helvetica,Arial; font-size:10pt; color:#010100">
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<table width="100%" border="0" cellpadding="0" cellspacing="0"><tr valign="top"><td width="28"></td><td><span style="font-family:Helvetica,Arial; font-size:10pt; color:#010100"></span></span></span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><span style="font-family:Helvetica,Arial; font-size:10pt; color:#010100">( </span></span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><span style="font-family:Helvetica,Arial; font-size:10pt; color:#010100"><i>column_name</i></span></span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><span style="font-family:Helvetica,Arial; font-size:10pt; color:#010100"> [ ASC | DESC ]  [ CASE | NOCASE ]  [, ... ] )</span></span><span style="font-family:Times New Roman; font-size:12pt; color:#000000">
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<b>Description
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</span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000">CREATE INDEX constructs an index <i>index_name</i> on the specified table. Indexes are primarily used to enhance database performance (though inappropriate use will result in slower performance).
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Multi-column indexes are allowed.
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</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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UNIQUE
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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">Causes the database engine to check for duplicate values in the table when the index is created (if data already exist) and each time data is added. Attempts to insert or update data which would result in duplicate entries will generate an error.
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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>index_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 index to be created.
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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">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></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>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 the table to be removed.
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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_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 to be indexed.</span></span><span style="font-family:Times New Roman; font-size:12pt; color:#000000"> 
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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:Times New Roman; font-size:12pt; color:#000000"></span></td></tr></table><span style="font-family:Times New Roman; font-size:12pt; 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">ASC
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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 column will be indexed with ascending sort order.</span></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">This is the default.</span><span style="font-family:Times New Roman; font-size:12pt; color:#000000">
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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:Times New Roman; font-size:12pt; color:#000000"></span></td></tr></table><span style="font-family:Times New Roman; font-size:12pt; 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">DESC<i> </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 column will be indexed with descending sort order.</span></span><span style="font-family:Times New Roman; font-size:12pt; color:#000000">
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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:Times New Roman; font-size:12pt; color:#000000"></span></td></tr></table><span style="font-family:Times New Roman; font-size:12pt; 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">CASE
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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 column will be indexed with case-sensitive sort order.</span></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">This is the default.</span><span style="font-family:Times New Roman; font-size:12pt; color:#000000">
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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:Times New Roman; font-size:12pt; color:#000000"></span></td></tr></table><span style="font-family:Times New Roman; font-size:12pt; 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">NOCASE<i> </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 column will be indexed with case-insensitive sort order.</span></span><span style="font-family:Times New Roman; font-size:12pt; color:#000000">
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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:Times New Roman; font-size:12pt; color:#000000"></span></td></tr></table><span style="font-family:Times New Roman; font-size:12pt; color:#000000">
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</span><span style="font-family:Helvetica,Arial; font-size:10pt; color:#000000"><b>Example:
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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">CREATE UNIQUE INDEX idxUniqueName ON  developers (name DESC NOCASE, code);
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