<p>Hello all, I have alot of experience with relational databases in other languages (php, c#, java, etc) but whenever i try to use the sql package in go it feels superrrr clunky.... how do you guys deal with nulls? (i like using deletedAt nullable date time columns) I hate having to use things like sql.NullString and I especially hate having to use mysql.NullTime because it kills my portability. Right now Im leaning twords using <a href="https://github.com/boltdb/bolt">https://github.com/boltdb/bolt</a> but I like relational DB's....</p>
<p>It just feels clunky...</p>
<p>edit: preliminary tests show that you can use string/date pointers rather then sql.NullString, I need to explore this further....</p>
<p>thanks <a href="/u/TheMerovius">/u/TheMerovius</a></p>
<hr/>**评论：**<br/><br/>twek: <pre><p>Im going to give this a try i think...</p>
<p><a href="http://jmoiron.github.io/sqlx/" rel="nofollow">http://jmoiron.github.io/sqlx/</a></p></pre>BoTuLoX: <pre><p>It adds some nifty functionality. To deal with nullable time I just make it a pointer.</p></pre>twek: <pre><p>yeah thats where im getting too... I really dislike those nullable structs pointers seem nicer</p></pre>Growlizing: <pre><p>I also found it extremely clunky. Something like gorp did help me though, which I've now started using for rdbms.</p></pre>twek: <pre><p>glad im not the only one! I looked at gorp but gorm seemed more supported and it wasnt very unclunky either</p></pre>Growlizing: <pre><p>Yeah, well, I'm too scarred from java and ruby world I think to ever use a full ORM again :(</p></pre>twek: <pre><p>I know that feeling.</p>
<p>In java i roll my own DAO's using springs NamedJDBCTemplate</p>
<p>its the only spring i can stomach</p></pre>TheMerovius: <pre><p>a) If your data can't be NULL, use <code>string</code>. If your data <em>can</em> be NULL, you'll have to use <code>sql.NullString</code> or something like it anyway. I don't see, how that affects your "portability"? (I think… maybe? You can also use a pointer. Not sure)</p>
<p>b) If you don't want to put <code>sql.NullString</code> like things into your struct, you can scan into an anonymous struct and then manually copy the fields over with whatever logic you like.</p>
<p>But I find it difficult seeing your problem. I don't see how PHP specifically makes this easier?</p></pre>twek: <pre><p>the portability problem comes from the fact that the standard sql package does not contain a sql.NullDate so you have to use mysql.NullDate which locks you to the mysql package (not sure if theres an alternative in sqlite etc packages) I havnt tried a date pointer... Ill have to try that. </p>
<p>I thought about the anonymous struct thing and its probably my best bet (because yes i dont like sql.NullString in my struct if i can help it)</p>
<p>Im not having any PROBLEMS (i.e the code works)</p>
<p>but the development of said code feels clunky is all... and when that happens I like to think theres a better way.</p></pre>TheMerovius: <pre><blockquote>
<p>the portability problem comes from the fact that the standard sql package does not contain a sql.NullDate so you have to use mysql.NullDate which locks you to the mysql package (not sure if theres an alternative in sqlite etc packages) I havnt tried a date pointer... Ill have to try that.</p>
</blockquote>
<p>You can use a mysql.NullDate with any other sql driver too. Or just copy-paste the type into your own code and use that (then you don't need to import the mysql-driver.</p>
<p>Also, in my experience, every SQL database has a different feature-set (in particular, dates are AFAIK one of the things that differ wildly) so you very probably are not portable between databases anyway. :)</p>
<blockquote>
<p>and when that happens I like to think theres a better way.</p>
</blockquote>
<p>I like sqlx whenever I need SQL stuff :) It gives a good tradeoff between simplicity and power, IMHO.</p>
<p>[edit] To elaborate on portability: For example, how you give placeholder in prepared statements varies, sometimes you need positional arguments, sometimes you need '?' (I think mysql does that) and sometimes both work.</p></pre>twek: <pre><p>I have not tried sqlx yet but just the fact that I can use pointers in my structs rather then sql.Null**** is already a great win, the alternative is to write a nice search feature for boltdb. Which would give me an excuse to brush up on cool stuff like breadth first search and graphs....</p></pre>twek: <pre><p>And php/java etc make this easier by allowing nullable primitives </p></pre>TheMerovius: <pre><p><code>sql.NullString</code> is a "nullable primitive". It gives you <em>precisely</em> the same semantics, just slightly different syntax.</p></pre>twek: <pre><p>Well its a struct not a primitive</p></pre>TheMerovius: <pre><p>As I said, it gives you precisely the same semantics. You just have to write <code>if !nullString.Valid()</code> instead of <code>if (!defined null_string)</code>, or however you check for undefinednes in PHP and use <code>nullString.Value()</code>, instead of <code>null_string</code>. You are splitting hairs.</p></pre>WellAdjustedOutlaw: <pre><p>A word of warning. If you think a key/value store is going to help you when you need an rdbms, you're in for a world of hurt. Also, if you think using and learning a new db is going to be a cakewalk vs the probably years of experience you have with something like MySQL, you're going to have a very bumpy ride. Just my $0.02</p>
<p>I found the Go approach to databases a bit wonky until I understood Go more. Not that I'm good now, I just seem to understand other Golang developers' intentions more readily now. /shrug</p></pre>twek: <pre><p>Luckily I also have years of experience with writing various btree key value stores, for my application to work I would just have to write an efficient search for boltdb I was thinking a dictionary with a graph like component... iono Ill probably just use mysql and pointers</p></pre>ptman: <pre><p>Not all Go ORMs can handle pointers to time.Time: <a href="https://github.com/astaxie/beego/issues/1019" rel="nofollow">https://github.com/astaxie/beego/issues/1019</a></p></pre>
