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https://issues.apache.org/jira/browse/PHOENIX-476?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15562842#comment-15562842
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James Taylor commented on PHOENIX-476:
--------------------------------------
Thanks, [~kliew]. Looking very good. Couple of comments:
- Why do you say that without caching expression we can only compile literals?
The SQLParser.parseExpression() call will happily parse any expression and the
ExpressionCompiler will translate from the ParseNode to an Expression. The
caching of expressions was just an optimization, not a requirement. Also, we
don't parse negative literals because it leads to problems with certain
expressions. For example, QueryParserTest.testSubtractionInSelect doesn't pass
with your patch applied.
- Minor, but I think the change to this file can be reverted:
{code}
diff --git
a/phoenix-core/src/main/java/org/apache/phoenix/schema/MetaDataClient.java
b/phoenix-core/src/main/java/org/apache/phoenix/schema/MetaDataClient.java
index 1e635d8..f617f92 100644
--- a/phoenix-core/src/main/java/org/apache/phoenix/schema/MetaDataClient.java
+++ b/phoenix-core/src/main/java/org/apache/phoenix/schema/MetaDataClient.java
@@ -431,7 +431,7 @@ public class MetaDataClient {
/**
* Update the cache with the latest as of the connection scn.
- * @param functioNames
+ * @param functionNames
* @return the timestamp from the server, negative if the function was
added to the cache and positive otherwise
* @throws SQLException
*/
{code}
If you can undo the changes for the parser for negative literals, use
SQLParser.parseExpression() instead of parseLiteral(), add a few of your test
back that use expressions instead of literals, and ensure that all unit tests
pass (i.e. run {{mvn verify}}), then I think we'll be good to go.
> Support declaration of DEFAULT in CREATE statement
> --------------------------------------------------
>
> Key: PHOENIX-476
> URL: https://issues.apache.org/jira/browse/PHOENIX-476
> Project: Phoenix
> Issue Type: Task
> Affects Versions: 3.0-Release
> Reporter: James Taylor
> Assignee: Kevin Liew
> Labels: enhancement
> Attachments: PHOENIX-476.2.patch, PHOENIX-476.3.patch,
> PHOENIX-476.4.patch, PHOENIX-476.5.patch, PHOENIX-476.6.patch,
> PHOENIX-476.patch
>
>
> Support the declaration of a default value in the CREATE TABLE/VIEW statement
> like this:
> CREATE TABLE Persons (
> Pid int NOT NULL PRIMARY KEY,
> LastName varchar(255) NOT NULL,
> FirstName varchar(255),
> Address varchar(255),
> City varchar(255) DEFAULT 'Sandnes'
> )
> To implement this, we'd need to:
> 1. add a new DEFAULT_VALUE key value column in SYSTEM.TABLE and pass through
> the value when the table is created (in MetaDataClient).
> 2. always set NULLABLE to ResultSetMetaData.columnNoNulls if a default value
> is present, since the column will never be null.
> 3. add a getDefaultValue() accessor in PColumn
> 4. for a row key column, during UPSERT use the default value if no value was
> specified for that column. This could be done in the PTableImpl.newKey method.
> 5. for a key value column with a default value, we can get away without
> incurring any storage cost. Although a little bit of extra effort than if we
> persisted the default value on an UPSERT for key value columns, this approach
> has the benefit of not incurring any storage cost for a default value.
> * serialize any default value into KeyValueColumnExpression
> * in the evaluate method of KeyValueColumnExpression, conditionally use
> the default value if the column value is not present. If doing partial
> evaluation, you should not yet return the default value, as we may not have
> encountered the the KeyValue for the column yet (since a filter evaluates
> each time it sees each KeyValue, and there may be more than one KeyValue
> referenced in the expression). Partial evaluation is determined by calling
> Tuple.isImmutable(), where false means it is NOT doing partial evaluation,
> while true means it is.
> * modify EvaluateOnCompletionVisitor by adding a visitor method for
> RowKeyColumnExpression and KeyValueColumnExpression to set
> evaluateOnCompletion to true if they have a default value specified. This
> will cause filter evaluation to execute one final time after all KeyValues
> for a row have been seen, since it's at this time we know we should use the
> default value.
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