How to use
Metadata
in
org.apache.calcite.rel.metadata

Best Java code snippets using org.apache.calcite.rel.metadata.Metadata (Showing top 3 results out of 315)

Common ways to obtain Metadata

private void myMethod () {
 Metadata m =UnboundMetadata unboundMetadata;RelNode rel;RelMetadataQuery mq;unboundMetadata.bind(rel, mq)
Smart code suggestions by Tabnine
}

builder.add(metadata.rel());
if (args != null) {
 for (Object arg : args) {
long timestamp = planner.getRelMetadataTimestamp(metadata.rel());

builder.add(metadata.rel());
if (args != null) {
 for (Object arg : args) {
long timestamp = planner.getRelMetadataTimestamp(metadata.rel());

builder.add(method);
builder.add(metadata.rel());
if (args != null) {
 for (Object arg : args) {
CacheKey key = new CacheKey(internalKey);
long timestamp = planner.getRelMetadataTimestamp(metadata.rel());

Javadoc

Metadata about a relational expression.

For particular types of metadata, a sub-class defines one of more methods to query that metadata. Then a RelMetadataProvider can offer those kinds of metadata for particular sub-classes of RelNode.

User code (typically in a planner rule or an implementation of RelNode#computeSelfCost(org.apache.calcite.plan.RelOptPlanner,RelMetadataQuery)) acquires a Metadata instance by calling RelNode#metadata.

A Metadata instance already knows which particular RelNodeit is describing, so the methods do not pass in the RelNode. In fact, quite a few metadata methods have no extra parameters. For instance, you can get the row-count as follows:

 
RelNode rel; 
double rowCount = rel.metadata(RowCount.class).rowCount();

Most used methods

rel
Returns the relational expression that this metadata is about.

Popular in Java

Start an intent from android
addToBackStack (FragmentTransaction)
getExternalFilesDir (Context)
getSupportFragmentManager (FragmentActivity)
BufferedWriter (java.io)
Wraps an existing Writer and buffers the output. Expensive interaction with the underlying reader is
URL (java.net)
A Uniform Resource Locator that identifies the location of an Internet resource as specified by RFC
URLConnection (java.net)
A connection to a URL for reading or writing. For HTTP connections, see HttpURLConnection for docume
Charset (java.nio.charset)
A charset is a named mapping between Unicode characters and byte sequences. Every Charset can decode
Connection (java.sql)
A connection represents a link from a Java application to a database. All SQL statements and results
HashMap (java.util)
HashMap is an implementation of Map. All optional operations are supported.All elements are permitte
Top plugins for WebStorm

How to useMetadata in org.apache.calcite.rel.metadata

Best Java code snippets using org.apache.calcite.rel.metadata.Metadata (Showing top 3 results out of 315)

How to use
Metadata
in
org.apache.calcite.rel.metadata