How to DELETE using multiple WHERE clauses [SQLITE] -


first question ask is, faster make 1 delete query multiple clauses, or faster 1 one? , second if how make delete query multiple clauses? in advance!

you can't have more 1 where clause, can make condition more complex.

if table has firstname , lastname, , want delete john doe, toby steed, , linda powers, combine and , or conditions this:

delete mytable  ( firstname = 'john' , lastname = 'doe' )     or ( firstname = 'toby' , lastname = 'steed' )     or ( firstname = 'linda' , lastname = 'powers' )

now, if java, shouldn't (ever!) use string concatenation build sql statement that. use preparedstatement:

string sql = "delete mytable" +              " ( firstname = ? , lastname = ? )" +                 " or ( firstname = ? , lastname = ? )" +                 " or ( firstname = ? , lastname = ? )"; try (preparedstatement stmt = conn.preparestatement(sql)) {     stmt.setstring(1, "john");     stmt.setstring(2, "doe");     stmt.setstring(3, "toby");     stmt.setstring(4, "steed");     stmt.setstring(5, "linda");     stmt.setstring(6, "powers");     stmt.executeupdate(); }

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