Merge pull request #5774 from cockroachdb/20191104-zigzag-joins

Note that zigzag joins are on by default in 19.2
cockroachdb · Nov 6, 2019 · ca534d2 · ca534d2
2 parents e33e16c + 54cde4e
commit ca534d2
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diff --git a/_includes/v19.2/misc/session-vars.html b/_includes/v19.2/misc/session-vars.html
@@ -95,6 +95,18 @@
    <td>Yes</td>
   </tr>
 
+  <tr>
+   <td>
+    <code>enable_zig_zag_join</code>
+   </td>
+   <td>Indicates whether the <a href="cost-based-optimizer.html">cost-based optimizer</a> will plan certain queries using a zig-zag merge join algorithm, which searches for the desired intersection by jumping back and forth between the indexes based on the fact that after constraining indexes, they share an ordering. </td>
+   <td>
+    <code>on</code>
+   </td>
+   <td>Yes</td>
+   <td>Yes</td>
+  </tr>
+
   <tr>
    <td>
     <code>extra_float_digits</code>

diff --git a/v19.2/experimental-features.md b/v19.2/experimental-features.md
@@ -20,8 +20,7 @@ The table below lists the experimental session settings that are available.  For
 | Variable                            | Default Value | Description                                                                                                                                                                                                                                                                                             |
 |-------------------------------------+---------------+---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
 | `experimental_force_split_at`       | `'off'`       | Indicates whether checks to prevent incorrect usage of [`ALTER TABLE ... SPLIT AT`](split-at.html) should be skipped.                                                                                                                                                                                   |
-| `experimental_enable_zigzag_join`   | `'off'`       | Indicates whether the [cost-based optimizer](cost-based-optimizer.html) will plan certain queries using a zig-zag merge join algorithm, which searches for the desired intersection by jumping back and forth between the indexes based on the fact that they share a sorted order in their key suffix. |
-| `experimental_serial_normalization` | `'rowid'`     | If set to `'virtual_sequence'`, make the [`SERIAL`](serial.html) pseudo-type optionally auto-create a sequence for [better compatibility with Hibernate sequences](https://forum.cockroachlabs.com/t/hibernate-sequence-generator-returns-negative-number-and-ignore-unique-rowid/).
+| `experimental_serial_normalization` | `'rowid'`     | If set to `'virtual_sequence'`, make the [`SERIAL`](serial.html) pseudo-type optionally auto-create a sequence for [better compatibility with Hibernate sequences](https://forum.cockroachlabs.com/t/hibernate-sequence-generator-returns-negative-number-and-ignore-unique-rowid/).                    |
 
 ## SQL statements