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DeleteRow removes the row indicated by the row cursor from the database.

The row cursor can be moved by calling Next , Previous , First , Last , and GotoRow .

Not all Result modules can be updated. Only Result modules representing tables containing data from a single table (no joins) and a column of primary keys are guaranteed to be updatable. Particular JDBC Drivers and databases may allow a wider range of updatable tables and thus Result modules.

$\mathrm{driver}≔\mathrm{Database}\left[\mathrm{LoadDriver}\right]\left(\right)\:$

$\mathrm{conn}≔\mathrm{driver}:-\mathrm{OpenConnection}\left(\mathrm{url}\,\mathrm{name}\,\mathrm{pass}\right)\:$$\mathrm{res}≔\mathrm{conn}:-\mathrm{ExecuteQuery}\left(''SELECT\; id,name,number,mass\; FROM\; animals''\right)\:$$\mathrm{res}:-\mathrm{ToMaple}\left(\mathrm{output}='\mathrm{Array}'\right)$

$\left[\begin{array}{cccc}1& ''fish''& 100& 0.0100000000000000002\\ 2& ''dog''& 10& 20.5000000000000000\\ 3& ''cat''& 10& 5.50000000000000000\\ 4& ''rat''& 50& 0.500000000000000000\\ 5& ''horse''& 3& 400.300000000000011\\ 6& ''snake''& 1& 7.75000000000000000\\ 7& ''lizard''& 5& 0.100000000000000004\\ 8& ''parrot''& 20& 2.\\ 9& ''pig''& 4& 10.\\ 10& ''hamster''& 30& 0.200000000000000012\end{array}\right]$

$\mathrm{res}:-\mathrm{First}\left(\right)$

$\mathrm{true}$

$\mathrm{res}:-\mathrm{GetRowIndex}\left(\right)$

$1$

$\mathrm{res}:-\mathrm{GetData}\left(''id''\right)$

$1$

$\mathrm{res}:-\mathrm{DeleteRow}\left(\right)\;$$\mathrm{res}:-\mathrm{First}\left(\right)$

$\mathrm{true}$

$\mathrm{res}:-\mathrm{ToMaple}\left(\mathrm{output}='\mathrm{Array}'\right)$

$\left[\begin{array}{cccc}2& ''dog''& 10& 20.5000000000000000\\ 3& ''cat''& 10& 5.50000000000000000\\ 4& ''rat''& 50& 0.500000000000000000\\ 5& ''horse''& 3& 400.300000000000011\\ 6& ''snake''& 1& 7.75000000000000000\\ 7& ''lizard''& 5& 0.100000000000000004\\ 8& ''parrot''& 20& 2.\\ 9& ''pig''& 4& 10.\\ 10& ''hamster''& 30& 0.200000000000000012\end{array}\right]$

$\mathrm{res}:-\mathrm{GotoRow}\left(5\right)$

$\mathrm{true}$

$\mathrm{res}:-\mathrm{GetRowIndex}\left(\right)$

$5$

$\mathrm{res}:-\mathrm{GetData}\left(''id''\right)$

$6$

$\mathrm{res}:-\mathrm{DeleteRow}\left(\right)\;$$\mathrm{res}:-\mathrm{First}\left(\right)$

$\mathrm{true}$

$\mathrm{res}:-\mathrm{ToMaple}\left(\mathrm{output}='\mathrm{Array}'\right)$

$\left[\begin{array}{cccc}2& ''dog''& 10& 20.5000000000000000\\ 3& ''cat''& 10& 5.50000000000000000\\ 4& ''rat''& 50& 0.500000000000000000\\ 5& ''horse''& 3& 400.300000000000011\\ 7& ''lizard''& 5& 0.100000000000000004\\ 8& ''parrot''& 20& 2.\\ 9& ''pig''& 4& 10.\\ 10& ''hamster''& 30& 0.200000000000000012\end{array}\right]$

$\mathrm{res}:-\mathrm{GotoRow}\left(7\right)$

$\mathrm{true}$

$\mathrm{res}:-\mathrm{GetRowIndex}\left(\right)$

$7$

$\mathrm{res}:-\mathrm{GetData}\left(''id''\right)$

$9$

$\mathrm{res}:-\mathrm{DeleteRow}\left(\right)\;$$\mathrm{res}≔\mathrm{conn}:-\mathrm{ExecuteQuery}\left(''SELECT\; id,name,number,mass\; FROM\; animals''\right)\:$$\mathrm{res}:-\mathrm{ToMaple}\left(\mathrm{output}='\mathrm{Array}'\right)$

$\left[\begin{array}{cccc}2& ''dog''& 10& 20.5000000000000000\\ 3& ''cat''& 10& 5.50000000000000000\\ 4& ''rat''& 50& 0.500000000000000000\\ 5& ''horse''& 3& 400.300000000000011\\ 7& ''lizard''& 5& 0.100000000000000004\\ 8& ''parrot''& 20& 2.\\ 10& ''hamster''& 30& 0.200000000000000012\end{array}\right]$