Programming Groovy 2

9.3 Database Select

We can use the ​Sql​ object to conveniently iterate through data in a table. Simply call the ​eachRow​ method, provide it with a SQL query to execute, and give it a closure to process each row of data, thusly:

println "City                Temperature"
sql.eachRow('SELECT * from weather') {
  printf "%-20s%s\n", it.city, it[1]
}

The data fetched using the previous code is as follows:

City                Temperature
Austin              48
Baton Rouge         57
Jackson             50
Montgomery          53
Phoenix             67
Sacramento          66
Santa Fe            27
Tallahassee         59

We asked ​eachRow​ to execute the SQL query on the ​weather​ table to process all its rows. We then iterated (as the name ​each​ indicates) over each row. There’s more grooviness here—we ...