equal
deleted
inserted
replaced
28 <strong>SQL transformation</strong>: |
28 <strong>SQL transformation</strong>: |
29 SQL is one of most powerful languages for processing relational data and the most widespread one. |
29 SQL is one of most powerful languages for processing relational data and the most widespread one. |
30 Now it can be used even on-the-fly in shell pipelines – without having any database server running. |
30 Now it can be used even on-the-fly in shell pipelines – without having any database server running. |
31 It is useful for record filtering, JOINing several relations together, doing aggregations or computations. |
31 It is useful for record filtering, JOINing several relations together, doing aggregations or computations. |
32 By default everything is done in memory, but with the <code>--file</code> parameter we can use a temporary file |
32 By default everything is done in memory, but with the <code>--file</code> parameter we can use a temporary file |
33 and with <code>--keep-file</code> we can make it not so temporary. |
33 and with <code>--keep-file</code> we can make it not so temporary (n.b. in the next version this option was renamed to <code>--file-keep</code>). |
34 This tool uses the <a href="https://www.sqlite.org/">SQLite</a> library. |
34 This tool uses the <a href="https://www.sqlite.org/">SQLite</a> library. |
35 </li> |
35 </li> |
36 |
36 |
37 <li> |
37 <li> |
38 <strong>file system input</strong>: |
38 <strong>file system input</strong>: |