gudusoft.gsqlparser.dlineage.util

Class PhysicalTableMergeKeys

Object

gudusoft.gsqlparser.dlineage.util.PhysicalTableMergeKeys

public final class PhysicalTableMergeKeys
extends Object

Merge keys of the physical tables and views of one output merge.

Two tables are one table exactly when their identities under the analysis's identifier rules agree, whatever their legacy folded names. A table carries its identity when its producer minted one (a table analyzed from SQL, a catalog table read by SQLEnvMetadataAnalyzer), or vouches that its published name is a SQL spelling (the SQLDep, Grabit and sqlflow readers), in which case the name read under this merge's rules is its identity. A table from a serialized document carries none: its published name is then the only evidence, and a weak one, since a stored name is published bare and reads as another name.

Decided after every table of the merge is known, and independently of the order they arrive in:

• a table carrying an identity is keyed by that identity;
• a table carrying none joins the one identity it can be shown to be: the identity of a table that published exactly the same name (the table reloaded, or its copy), else the identity its own published name reads as, if some table carries it; under a configured identifier profile its published name is its identity, as the configured-profile merge always read it;
• otherwise it keeps the legacy merge when no table of its legacy bucket has an identity, and stays apart when one does, rather than attaching to a guess.

An identity is keyed by the first legacy bucket it was seen in: the bucket's first identity by the legacy key itself, as before identities existed, so a merge that groups tables as it always did also orders its output as it always did; another identity of the bucket by the legacy key and its position.

Constructor Summary

Constructors

Constructor and Description
PhysicalTableMergeKeys(boolean configuredRules)

Method Summary

Modifier and Type	Method and Description
void	add(String legacyKey, QualifiedCanonKey carriedIdentity, String qualifiedTableName) First pass: one call per physical table or view of the merge, or per name addTable(gudusoft.gsqlparser.dlineage.dataflow.model.xml.table, java.lang.String, java.lang.String) registers.
void	addTable(table table, String legacyKey, String qualifiedTableName) First pass for one physical table or view: add(java.lang.String, gudusoft.gsqlparser.sqlenv.QualifiedCanonKey, java.lang.String) for the table under its own name and, for a merged table that carries an identity, under each exact name the carried tables merged into it published (table.getCarriedPublishedNames()), so a merge in stages matches a table that carries no identity on the evidence one merge of all the inputs has.
static QualifiedCanonKey	carriedIdentity(table table, String legacyKey, String qualifiedTableName) The identity a table carries: the one its producer minted, else its published name read under this analysis's rules when the producer vouches the name is a SQL spelling.
String	keyOf(String legacyKey, QualifiedCanonKey carriedIdentity, String qualifiedTableName) Second pass: the merge key of a table given to add(java.lang.String, gudusoft.gsqlparser.sqlenv.QualifiedCanonKey, java.lang.String).

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PhysicalTableMergeKeys

public PhysicalTableMergeKeys(boolean configuredRules)

Parameters:

configuredRules - whether the analysis runs under identifier rules of its own, rather than its vendor's defaults

Method Detail

carriedIdentity

public static QualifiedCanonKey carriedIdentity(table table,
                                                String legacyKey,
                                                String qualifiedTableName)

The identity a table carries: the one its producer minted, else its published name read under this analysis's rules when the producer vouches the name is a SQL spelling. Null for a table that carries none.

addTable

public void addTable(table table,
                     String legacyKey,
                     String qualifiedTableName)

First pass for one physical table or view: add(java.lang.String, gudusoft.gsqlparser.sqlenv.QualifiedCanonKey, java.lang.String) for the table under its own name and, for a merged table that carries an identity, under each exact name the carried tables merged into it published (table.getCarriedPublishedNames()), so a merge in stages matches a table that carries no identity on the evidence one merge of all the inputs has.

add

public void add(String legacyKey,
                QualifiedCanonKey carriedIdentity,
                String qualifiedTableName)

First pass: one call per physical table or view of the merge, or per name addTable(gudusoft.gsqlparser.dlineage.dataflow.model.xml.table, java.lang.String, java.lang.String) registers.

keyOf

public String keyOf(String legacyKey,
                    QualifiedCanonKey carriedIdentity,
                    String qualifiedTableName)

Second pass: the merge key of a table given to add(java.lang.String, gudusoft.gsqlparser.sqlenv.QualifiedCanonKey, java.lang.String).