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Tag: sql

Get minimum unused value in MySQL column

I have a table with integer ID column. I would like to get the minimum unused value for this column. The query should find the first hole in table IDs and get the minimum value inside it. I’ll try to explain it with some examples. Example 1: no-holes table In this case, I have a table without holes and …

Calculate Median with SQL (DB2)

I’m having issues calculating the median for my result set and could use some help. I need to provide the median, max, min, avg, and standard deviation. There are 222 rows which can be more or less and I’m not sure what I have so far is an accurate way of calculating the median. Here is my query. …

PostgreSQL:How get last rows from a select query

See the below example, And if I Execute Will Get So,How Can I Get the Last 2 Rows in select * from data? What I’m expecting is…. Answer You have two options according to your need i.e, Or LIMIT and OFFSET if you want the 4th and 5th row just offset the first 3 so that the 4th row becomes

SQL Server range indexing ideas

I need help understanding how to create proper indexing on a table for fast range selects. I have a table with the following columns: Column — Type frameidx — int u — int v — int x — float(53) y — float(53) z — float(53) None of these columns is unique. There are to b…

NVarChar to C# Data Types

The database stores nvarchar, I retrieve the information and I’d like to jam it into C# data types without any declarative conversion code. Can you implicitly convert nvarchar to C# data types? (e.g. nvarchar to int) Answer Nvarchar is a string, if you want to turn it in to a int you will have to go thr…

Can’t insert Cyrillic symbols into MySQL with JDBC

I have a web app which uses com.mysql.jdbc.Driver to connect to MySQL database. Here are jdbcMySQL.properties: I create database like this: And the problem is: if I make then I have in my table BUT, if I make: I have in my table: Answer MySQL is a bit crazy w.r.t. encodings, try: Furthermore there is one more…