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    <p>I recommend avoiding writing raw SQL, and, in this age, I'd use an ORM, even for simple DB use. I highly recommend using the <a href="http://sequel.rubyforge.org/documentation.html">Sequel</a> gem. Borrowing from an <a href="http://sequel.rubyforge.org/rdoc/files/README_rdoc.html">example</a> in the Sequel docs:</p> <pre><code>sequel sqlite://temp Your database is stored in DB... </code></pre> <p>Using SQLite, that started the sequel ORM in interactive mode, and created the SQLite database called "temp".</p> <pre><code>ruby-1.9.2-p290 :001 &gt; require 'logger' =&gt; true ruby-1.9.2-p290 :002 &gt; DB.loggers &lt;&lt; Logger.new(STDOUT) =&gt; [#&lt;Logger:0x0000010160bc40 @progname=nil, @level=0, @default_formatter=#&lt;Logger::Formatter:0x0000010160bc18 @datetime_format=nil&gt;, @formatter=nil, @logdev=#&lt;Logger::LogDevice:0x0000010160bbc8 @shift_size=nil, @shift_age=nil, @filename=nil, @dev=#&lt;IO:&lt;STDOUT&gt;&gt;, @mutex=#&lt;Logger::LogDevice::LogDeviceMutex:0x0000010160bba0 @mon_owner=nil, @mon_count=0, @mon_mutex=#&lt;Mutex:0x0000010160bb50&gt;&gt;&gt;&gt;] </code></pre> <p>That enabled logging so we can see what Sequel will do as it talks to the database.</p> <pre><code>ruby-1.9.2-p290 :003 &gt; items = DB[:items] # Create a dataset =&gt; #&lt;Sequel::SQLite::Dataset: "SELECT * FROM `items`"&gt; ruby-1.9.2-p290 :004 &gt; DB.tables I, [2011-11-25T10:17:13.056311 #10130] INFO -- : (0.000501s) SELECT * FROM `sqlite_master` WHERE (type = 'table' AND NOT name = 'sqlite_sequence') =&gt; [] </code></pre> <p>Doh! I forgot to create the table...</p> <pre><code>ruby-1.9.2-p290 :005 &gt; DB.create_table :items do ruby-1.9.2-p290 :006 &gt; primary_key :id ruby-1.9.2-p290 :007?&gt; String :name ruby-1.9.2-p290 :008?&gt; Float :price ruby-1.9.2-p290 :009?&gt; end I, [2011-11-25T10:17:20.985851 #10130] INFO -- : (0.002372s) CREATE TABLE `items` (`id` integer PRIMARY KEY AUTOINCREMENT, `name` varchar(255), `price` double precision) =&gt; nil </code></pre> <p>The table is created.</p> <pre><code>ruby-1.9.2-p290 :010 &gt; items = DB[:items] # Create a dataset =&gt; #&lt;Sequel::SQLite::Dataset: "SELECT * FROM `items`"&gt; </code></pre> <p>That created a dataset, which is just a convenient way to talk to a table.</p> <p>And, that's the payoff:</p> <pre><code>ruby-1.9.2-p290 :011 &gt; items.insert(:name =&gt; "Joan d'Arc") I, [2011-11-25T10:17:45.186945 #10130] INFO -- : (0.001981s) INSERT INTO `items` (`name`) VALUES ('Joan d''Arc') =&gt; 1 </code></pre> <p>The ORM automatically escapes the characters for you. Your job is simplified greatly.</p> <p>ORMs are DBM aware, so they know when to escape for a particular database. Your code doesn't change. It's trivial to switch from SQLite to MySQL, Postgres, or even non-SQL databases.</p>
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    1. CODoes Sequel work on a legacy database? I can only run the insert queries on the database.
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    2. COOf course. It's great with them. I use Sequel at work to talk to legacy MySQL and MSSQL DBs all the time. You can use it in the "dataset" mode, which is in my example, or you can have it work in full object mode using models for your tables, allowing full relational interlinking of the tables in your lookups and inserts. It's very smart and generates terse SQL and doesn't bog down the server with dumb queries. It's one of the best gems out there. Plus Jeremy Evans, who supports it, is a member here. You'll get responses to questions from him occasionally.
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    3. COIll try it. Thanks for the good explanation.
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