Remove Filter.sql

sql/catalyst/src/main/scala/org/apache/spark/sql/sources/filters.scala

@@ -36,18 +36,10 @@ abstract class Filter {
    */
   def references: Array[String]
 
-  def sql: String
-
   protected def findReferences(value: Any): Array[String] = value match {
     case f: Filter => f.references
     case _ => Array.empty
   }
-
-  protected def quoteIdentifier(name: String): String = {
-    // Escapes back-ticks within the identifier name with double-back-ticks, and then quote the
-    // identifier with back-ticks.
-    "`" + name.replace("`", "``") + "`"
-  }
 }
 
 /**
@@ -58,8 +50,6 @@ abstract class Filter {
  */
 @Stable
 case class EqualTo(attribute: String, value: Any) extends Filter {
-  def symbol: String = "="
-  override def sql: String = s"(${quoteIdentifier(attribute)} $symbol ${value.toString})"
   override def references: Array[String] = Array(attribute) ++ findReferences(value)
 }
 
@@ -72,8 +62,6 @@ case class EqualTo(attribute: String, value: Any) extends Filter {
  */
 @Stable
 case class EqualNullSafe(attribute: String, value: Any) extends Filter {
-  def symbol: String = "<=>"
-  override def sql: String = s"(${quoteIdentifier(attribute)} $symbol ${value.toString})"
   override def references: Array[String] = Array(attribute) ++ findReferences(value)
 }
 
@@ -85,8 +73,6 @@ case class EqualNullSafe(attribute: String, value: Any) extends Filter {
  */
 @Stable
 case class GreaterThan(attribute: String, value: Any) extends Filter {
-  def symbol: String = ">"
-  override def sql: String = s"(${quoteIdentifier(attribute)} $symbol ${value.toString})"
   override def references: Array[String] = Array(attribute) ++ findReferences(value)
 }
 
@@ -98,8 +84,6 @@ case class GreaterThan(attribute: String, value: Any) extends Filter {
  */
 @Stable
 case class GreaterThanOrEqual(attribute: String, value: Any) extends Filter {
-  def symbol: String = ">="
-  override def sql: String = s"(${quoteIdentifier(attribute)} $symbol ${value.toString})"
   override def references: Array[String] = Array(attribute) ++ findReferences(value)
 }
 
@@ -111,8 +95,6 @@ case class GreaterThanOrEqual(attribute: String, value: Any) extends Filter {
  */
 @Stable
 case class LessThan(attribute: String, value: Any) extends Filter {
-  def symbol: String = "<"
-  override def sql: String = s"(${quoteIdentifier(attribute)} $symbol ${value.toString})"
   override def references: Array[String] = Array(attribute) ++ findReferences(value)
 }
 
@@ -124,8 +106,6 @@ case class LessThan(attribute: String, value: Any) extends Filter {
  */
 @Stable
 case class LessThanOrEqual(attribute: String, value: Any) extends Filter {
-  def symbol: String = "<="
-  override def sql: String = s"(${quoteIdentifier(attribute)} $symbol ${value.toString})"
   override def references: Array[String] = Array(attribute) ++ findReferences(value)
 }
 
@@ -153,8 +133,6 @@ case class In(attribute: String, values: Array[Any]) extends Filter {
     s"In($attribute, [${values.mkString(",")}])"
   }
 
-  override def sql: String = s"${quoteIdentifier(attribute)} IN (${values.mkString(",")})"
-
   override def references: Array[String] = Array(attribute) ++ values.flatMap(findReferences)
 }
 
@@ -165,7 +143,6 @@ case class In(attribute: String, values: Array[Any]) extends Filter {
  */
 @Stable
 case class IsNull(attribute: String) extends Filter {
-  override def sql: String = s"(${quoteIdentifier(attribute)} IS NULL)"
   override def references: Array[String] = Array(attribute)
 }
 
@@ -176,7 +153,6 @@ case class IsNull(attribute: String) extends Filter {
  */
 @Stable
 case class IsNotNull(attribute: String) extends Filter {
-  override def sql: String = s"(${quoteIdentifier(attribute)} IS NOT NULL)"
   override def references: Array[String] = Array(attribute)
 }
 
@@ -187,7 +163,6 @@ case class IsNotNull(attribute: String) extends Filter {
  */
 @Stable
 case class And(left: Filter, right: Filter) extends Filter {
-  override def sql: String = s"(${left.sql}) AND (${right.sql})"
   override def references: Array[String] = left.references ++ right.references
 }
 
@@ -198,7 +173,6 @@ case class And(left: Filter, right: Filter) extends Filter {
  */
 @Stable
 case class Or(left: Filter, right: Filter) extends Filter {
-  override def sql: String = s"(${left.sql}) OR (${right.sql})"
   override def references: Array[String] = left.references ++ right.references
 }
 
@@ -209,7 +183,6 @@ case class Or(left: Filter, right: Filter) extends Filter {
  */
 @Stable
 case class Not(child: Filter) extends Filter {
-  override def sql: String = s"NOT (${child.sql})"
   override def references: Array[String] = child.references
 }
 
@@ -221,7 +194,6 @@ case class Not(child: Filter) extends Filter {
  */
 @Stable
 case class StringStartsWith(attribute: String, value: String) extends Filter {
-  override def sql: String = s"${quoteIdentifier(attribute)} LIKE '${value.toString}%'"
   override def references: Array[String] = Array(attribute)
 }
 
@@ -233,7 +205,6 @@ case class StringStartsWith(attribute: String, value: String) extends Filter {
  */
 @Stable
 case class StringEndsWith(attribute: String, value: String) extends Filter {
-  override def sql: String = s"${quoteIdentifier(attribute)} LIKE '%${value.toString}'"
   override def references: Array[String] = Array(attribute)
 }
 
@@ -245,7 +216,6 @@ case class StringEndsWith(attribute: String, value: String) extends Filter {
  */
 @Stable
 case class StringContains(attribute: String, value: String) extends Filter {
-  override def sql: String = s"${quoteIdentifier(attribute)} LIKE '%${value.toString}%'"
   override def references: Array[String] = Array(attribute)
 }
 
@@ -254,7 +224,6 @@ case class StringContains(attribute: String, value: String) extends Filter {
  */
 @Evolving
 case class AlwaysTrue() extends Filter {
-  override def sql: String = "TRUE"
   override def references: Array[String] = Array.empty
 }
 
@@ -267,7 +236,6 @@ object AlwaysTrue extends AlwaysTrue {
  */
 @Evolving
 case class AlwaysFalse() extends Filter {
-  override def sql: String = "FALSE"
   override def references: Array[String] = Array.empty
 }