Question

Suppose I have a database data1 which gives me this:

show tables;

---

table1

table2

table3

---

Now instead of individually executing “select * from each table” i want to create a procedure which goes through each database shown in “show databases;” resultset, and then executes select * from each table of that database. I thought of using cursors which would scroll down the resultset, hold each database name in a variable and then execute select statement on each table of that database traversing in the same way. Can someone kindly help me out with how to use cursors in this case, as i am only aware of using cursors for SELECT and UPDATE statements.

btw i use MYSQL.

Answer 1

I’ll refrain from asking why you would do this. Here is a general strategy in pseudocode;

[words in parentheses are (SQL commands and tables) which will run on your mySQL server.]

Connect to your mySQL server with your favourite tool/programming language and:

-- (USE information_schema;)

for db in (select distinct table_schema from tables;)
do:    
    for table in (select table_name from tables where table_schema='$db';)
    do:
        select field,column,attribute from $table;
    done
done

Good luck!