![]() Read our article about RDBMS bind variable casting madness for more information. ![]() With other databases, that’s a different story. Oracle can infer a lot of types for your bind variables, such that casting is almost never necessary. Oracle is actually very lenient and nice to use when it comes to bind variables. If you think that this is an Oracle issue, think again. If you’re using jOOQ 3.5 or later, you can take advantage of jOOQ’s new custom type binding feature, which works out of the box with Oracle, and transparently renders that CAST(? AS DATE) for you, only on those columns that are really relevant. If you’re using JPA / Hibernate, you can only hope that they got it right, because you probably won’t be able to fix those queries, otherwise. Tomorrow, another statement would suddenly pop up in your DBA’s reports. Of course, you could run AWR reports to find the worst statements in production and fix only those, but chances are that you won’t be able to fix your statements so easily and deploy them so quickly, so you might want to get it right in advance. If you’re using JDBC directly, you’re pretty much doomed. You have to do that every time you bind a variable to an Oracle DATE value, at least when used in predicates. PreparedStatement stmt = connection.prepareStatement( Let’s assume you have a range predicate like so: So, it’s always a safe bet to use types in Java, when you’re operating with Oracle DATE.īut things can go very wrong when you bind such variables via JDBC as can be seen in this Stack Overflow question here. Most legacy databases actually use DATE precisely for that, to store timestamps with no fractional seconds, such as: a timestamp with a fractional second precision of zero. Oracle’s DATE type is really a TIMESTAMP(0), i.e. ![]() ![]() Well, we all know that Oracle’s DATE is not really a date as in the SQL standard, or as in all the other databases, or as in. The only actually reasonable slide to follow the previous two is this one: Isn’t it horrible to make empty string the same thing as NULL? Please, Oracle… In my SQL talks at conferences, I love to confuse people with the following Oracle facts: ![]()
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