org.apache.spark.sql.catalyst.identifiers.scala Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.spark.sql.catalyst
/**
* An identifier that optionally specifies a database.
*
* Format (unquoted): "name" or "db.name"
* Format (quoted): "`name`" or "`db`.`name`"
*/
sealed trait IdentifierWithDatabase {
val identifier: String
def database: Option[String]
/*
* Escapes back-ticks within the identifier name with double-back-ticks.
*/
private def quoteIdentifier(name: String): String = name.replace("`", "``")
def quotedString: String = {
val replacedId = quoteIdentifier(identifier)
val replacedDb = database.map(quoteIdentifier(_))
if (replacedDb.isDefined) s"`${replacedDb.get}`.`$replacedId`" else s"`$replacedId`"
}
def unquotedString: String = {
if (database.isDefined) s"${database.get}.$identifier" else identifier
}
override def toString: String = quotedString
}
/**
* Encapsulates an identifier that is either a alias name or an identifier that has table
* name and optionally a database name.
* The SubqueryAlias node keeps track of the qualifier using the information in this structure
* @param identifier - Is an alias name or a table name
* @param database - Is a database name and is optional
*/
case class AliasIdentifier(identifier: String, database: Option[String])
extends IdentifierWithDatabase {
def this(identifier: String) = this(identifier, None)
}
object AliasIdentifier {
def apply(identifier: String): AliasIdentifier = new AliasIdentifier(identifier)
}
/**
* Identifies a table in a database.
* If `database` is not defined, the current database is used.
* When we register a permanent function in the FunctionRegistry, we use
* unquotedString as the function name.
*/
case class TableIdentifier(table: String, database: Option[String])
extends IdentifierWithDatabase {
override val identifier: String = table
def this(table: String) = this(table, None)
}
/** A fully qualified identifier for a table (i.e., database.tableName) */
case class QualifiedTableName(database: String, name: String) {
override def toString: String = s"$database.$name"
}
object TableIdentifier {
def apply(tableName: String): TableIdentifier = new TableIdentifier(tableName)
}
/**
* Identifies a function in a database.
* If `database` is not defined, the current database is used.
*/
case class FunctionIdentifier(funcName: String, database: Option[String])
extends IdentifierWithDatabase {
override val identifier: String = funcName
def this(funcName: String) = this(funcName, None)
override def toString: String = unquotedString
}
object FunctionIdentifier {
def apply(funcName: String): FunctionIdentifier = new FunctionIdentifier(funcName)
}