V$SqlStats vs V$SqlStats_Plan_Hash, different columns? Mustafa, 2020-07-012020-07-01 Hi there, V$SQLSTATSis a beautiful view for information about sql statements. you might say v$sql has that information too which is correct but V$SQLSTATSis much more faster than v$sql and keeps data about sql statements for a longer time than v$sql. https://docs.oracle.com/en/database/oracle/oracle-database/19/refrn/V-SQLSTATS.html However, the V$SQLSTATS view differs from V$SQL and V$SQLAREA in that it is faster,… Continue Reading
Performance Gain of NOCOPY Parameters Mustafa, 2020-06-262022-08-31 Hi, Almost every Oracle database uses PLSQL codes like packages/procedures/functions etc. Complex systems with complex codes pass many arguments (parameters) many times between plsql objects. Passing parameters might be the most executed operations in a database. So how well do you pass your parameters? I assume you know about types… Continue Reading
Oracle Join Methods Mustafa, 2020-06-262020-06-26 Hi, Actually I won’t explain anything today. I will just share a video by Chris Saxon who is also from askTom team. Great guy, you should also follow him. So he made a great, so simple and explanatory video that I have ever seen. Many thanks to Chris. Please watch. Continue Reading
Min/Max on same column Mustafa, 2020-05-222020-05-22 Hi, Let’s do a simple trick. You want to get min and max value of a column which is already indexed. As you know if you have an btree index on a column and try to get a Min or Max value then you will see an “Index Full Scan(Min/Max)”… Continue Reading
Oracle 18c New feature Private Temporary Table Mustafa, 2020-03-22 Hello, 18c introduced a new object called Private Temporary Table (I will call it PTT in this post). PTT is just another version of Global Temporary Table(GTT). The data is temporary and will be stored for a time. Data in temporary tables (both PTT and GTT) can be queried by… Continue Reading
How to store Yes No questions on table and BITAND function Mustafa, 2020-01-20 Hi everyone, you might see BITAND function is frequently used by Oracle on source codes. Did you wonder why? What does BITAND function do? as you can understand from the name, it does a bitwise AND operation on parameters. probably you know what a bitwise and but as a small… Continue Reading
Commit Time for an Inserted Row in Oracle Mustafa, 2019-05-25 Hello everyone, This week, one of my customer have experienced a problem. They provide some Web Service to their suppliers and one of those web services creates some rows and then returns the response as successful operation but just after that, supplier queries the newly created those rows but they… Continue Reading
How to Get Your SID? USERENV vs V$MYSTAT! Mustafa, 2019-05-232020-07-05 Hello everyone, This is an easy question. How to find your own session SID and when you ask Google for it, you will find many answers. While reading some documents, I realized that some Gurus are using V$MYSTAT to get current SID: Oracle PL/SQL select sid from v$mystat where rownum=1; 1 select sid from v$mystat where rownum=1; I always prefer USERENV(‘SID’) context to get… Continue Reading
Goodbye Log Triggers Welcome Flashback Data Archive Mustafa, 2019-03-022020-10-25 Hello, I would like to talk about Flashback Data Archive (or Flashback Archive – FBA) in 12c. FBA was introduced in 11g. It is not new but it has very important new features that allow us to use FBA very efficiently and for free. I would like to talk about… Continue Reading