Package dev.frostlake.storage

Class ResultSetColumn

java.lang.Object

dev.frostlake.storage.ResultSetColumn

public class ResultSetColumn
extends Object

Constructor Summary

Constructors

Constructor	Description
ResultSetColumn(String name, DataType dataType)
ResultSetColumn(String name, DataType dataType, String tableName)
ResultSetColumn(String name, DataType dataType, String tableName, DataType staticType)
ResultSetColumn(String name, DataType dataType, String tableName, DataType staticType, boolean nullable)
ResultSetColumn(String name, DataType dataType, String tableName, DataType staticType, boolean nullable, boolean nullabilityKnown)
ResultSetColumn(String name, DataType dataType, String tableName, DataType staticType, boolean nullable, boolean nullabilityKnown, ValueRange valueRange)
ResultSetColumn(String name, DataType dataType, String tableName, DataType staticType, boolean nullable, boolean nullabilityKnown, ValueRange valueRange, DataType spelledNumber)

Method Summary

Modifier and Type	Method	Description
String	getCollation()	The collation this column's values compare under, or null when it carries none.
DataType	getDataType()
String	getName()
DataType	getSpelledNumber()	The NUMBER this column's values spell, or null — see TableColumn#getSpelledNumber.
DataType	getStaticType()	The type this column is statically KNOWN to produce, or null when a projection could not tell — in which case getDataType() is a placeholder that no type rule may read.
String	getTableName()
ValueRange	getValueRange()	The interval this column's values lie in, or null when none is known.
boolean	isNullabilityKnown()	Whether isNullable() was determined rather than defaulted.
boolean	isNullable()	Whether this column accepts NULL.
ResultSetColumn	withCollation(String spec)	This column carrying a collation — what a projection stamps when the expression it projects has one, so the derived relation, view or table built from this result set collates the column too.

Methods inherited from class java.lang.Object

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

Constructor Details

ResultSetColumn

public ResultSetColumn(String name,
 DataType dataType)

ResultSetColumn

public ResultSetColumn(String name,
 DataType dataType,
 String tableName)

ResultSetColumn

public ResultSetColumn(String name,
 DataType dataType,
 String tableName,
 DataType staticType)

ResultSetColumn

public ResultSetColumn(String name,
 DataType dataType,
 String tableName,
 DataType staticType,
 boolean nullable)

ResultSetColumn

public ResultSetColumn(String name,
 DataType dataType,
 String tableName,
 DataType staticType,
 boolean nullable,
 boolean nullabilityKnown)

ResultSetColumn

public ResultSetColumn(String name,
 DataType dataType,
 String tableName,
 DataType staticType,
 boolean nullable,
 boolean nullabilityKnown,
 ValueRange valueRange)

ResultSetColumn

public ResultSetColumn(String name,
 DataType dataType,
 String tableName,
 DataType staticType,
 boolean nullable,
 boolean nullabilityKnown,
 ValueRange valueRange,
 DataType spelledNumber)

Method Details

withCollation

public ResultSetColumn withCollation(String spec)

This column carrying a collation — what a projection stamps when the expression it projects has one, so the derived relation, view or table built from this result set collates the column too.

Parameters:

spec - the collation specification, lower-cased

Returns:

a copy of this column carrying it

getCollation

public String getCollation()

The collation this column's values compare under, or null when it carries none.

Returns:

the specification, lower-cased

getValueRange

public ValueRange getValueRange()

The interval this column's values lie in, or null when none is known.

getSpelledNumber

public DataType getSpelledNumber()

The NUMBER this column's values spell, or null — see TableColumn#getSpelledNumber.

getName

public String getName()

getDataType

public DataType getDataType()

getTableName

public String getTableName()

getStaticType

public DataType getStaticType()

The type this column is statically KNOWN to produce, or null when a projection could not tell — in which case getDataType() is a placeholder that no type rule may read. A derived table built from this result set carries the same distinction into the enclosing query.

isNullable

public boolean isNullable()

Whether this column accepts NULL. Only a projected COLUMN REFERENCE can answer false, and only when its source column is NOT NULL — an expression over that same column, a cast of it, an aggregate, a literal or either side of a set operation all accept NULL (live-verified).

isNullabilityKnown

public boolean isNullabilityKnown()

Whether isNullable() was determined rather than defaulted. Only a projected COLUMN REFERENCE determines it — an expression, an aggregate and a literal all leave it unknown, which is exactly the distinction the JDBC driver reports and the catalog surfaces do not.