Class CompareLike

java.lang.Object
org.h2.expression.Expression
org.h2.expression.condition.Condition
org.h2.expression.condition.CompareLike
All Implemented Interfaces:
HasSQL, Typed
public final class CompareLike extends Condition
Pattern matching comparison expression: WHERE NAME LIKE ?

  • Field Details

    • MATCH

      private static final int MATCH
      See Also:

    • ONE

      private static final int ONE
      See Also:

    • ANY

      private static final int ANY
      See Also:

    • compareMode

      private final CompareMode compareMode

    • defaultEscape

      private final String defaultEscape

    • likeType

      private final CompareLike.LikeType likeType

    • left

      private Expression left

    • not

      private final boolean not

    • whenOperand

      private final boolean whenOperand

    • escape

      private Expression escape

    • isInit

      private boolean isInit

    • patternChars

      private char[] patternChars

    • patternString

      private String patternString

    • patternTypes

      private int[] patternTypes
      one of MATCH / ONE / ANY

    • patternLength

      private int patternLength

    • patternRegexp

      private Pattern patternRegexp

    • ignoreCase

      private boolean ignoreCase

    • fastCompare

      private boolean fastCompare

    • invalidPattern

      private boolean invalidPattern

    • shortcutToStartsWith

      private boolean shortcutToStartsWith
      indicates that we can shortcut the comparison and use startsWith

    • shortcutToEndsWith

      private boolean shortcutToEndsWith
      indicates that we can shortcut the comparison and use endsWith

    • shortcutToContains

      private boolean shortcutToContains
      indicates that we can shortcut the comparison and use contains

  • Constructor Details

  • Method Details

    • getEscapeChar

      private static Character getEscapeChar(String s)

    • needParentheses

      public boolean needParentheses()
      Description copied from class: Expression
      Returns whether this expressions needs to be wrapped in parentheses when it is used as an argument of other expressions.
      Overrides:
      needParentheses in class Expression
      Returns:
      true if it is

    • getUnenclosedSQL

      public StringBuilder getUnenclosedSQL(StringBuilder builder, int sqlFlags)
      Description copied from class: Expression
      Get the SQL statement of this expression. This may not always be the original SQL statement, especially after optimization. Enclosing '(' and ')' are never appended.
      Specified by:
      getUnenclosedSQL in class Expression
      Parameters:
      builder - string builder
      sqlFlags - formatting flags
      Returns:
      the specified string builder

    • getWhenSQL

      public StringBuilder getWhenSQL(StringBuilder builder, int sqlFlags)
      Description copied from class: Expression
      Appends the SQL statement of this when operand to the specified builder.
      Overrides:
      getWhenSQL in class Expression
      Parameters:
      builder - string builder
      sqlFlags - formatting flags
      Returns:
      the specified string builder

    • optimize

      public Expression optimize(SessionLocal session)
      Description copied from class: Expression
      Try to optimize the expression.
      Specified by:
      optimize in class Expression
      Parameters:
      session - the session
      Returns:
      the optimized expression

    • getEscapeChar

      private Character getEscapeChar(Value e)

    • createIndexConditions

      public void createIndexConditions(SessionLocal session, TableFilter filter)
      Description copied from class: Expression
      Create index conditions if possible and attach them to the table filter.
      Overrides:
      createIndexConditions in class Expression
      Parameters:
      session - the session
      filter - the table filter

    • getValue

      public Value getValue(SessionLocal session)
      Description copied from class: Expression
      Return the resulting value for the current row.
      Specified by:
      getValue in class Expression
      Parameters:
      session - the session
      Returns:
      the result

    • getWhenValue

      public boolean getWhenValue(SessionLocal session, Value left)
      Description copied from class: Expression
      Return the resulting value of when operand for the current row.
      Overrides:
      getWhenValue in class Expression
      Parameters:
      session - the session
      left - value on the left side
      Returns:
      the result

    • getValue

      private Value getValue(SessionLocal session, Value left)

    • containsIgnoreCase

      private static boolean containsIgnoreCase(String src, String what)

    • compareAt

      private boolean compareAt(String s, int pi, int si, int sLen, char[] pattern, int[] types)

    • compare

      private boolean compare(char[] pattern, String s, int pi, int si)

    • isWhenConditionOperand

      public boolean isWhenConditionOperand()
      Description copied from class: Expression
      Returns whether this expression is a right side of condition in a when operand.
      Overrides:
      isWhenConditionOperand in class Expression
      Returns:
      true if it is, false otherwise

    • test

      public boolean test(String testPattern, String value, char escapeChar)
      Test if the value matches the pattern.
      Parameters:
      testPattern - the pattern
      value - the value
      escapeChar - the escape character
      Returns:
      true if the value matches

    • test

      public boolean test(String value)
      Test if the value matches the initialized pattern.
      Parameters:
      value - the value
      Returns:
      true if the value matches

    • initPattern

      public void initPattern(String p, Character escapeChar)
      Initializes the pattern.
      Parameters:
      p - the pattern
      escapeChar - the escape character

    • isFullMatch

      private boolean isFullMatch()

    • getNotIfPossible

      public Expression getNotIfPossible(SessionLocal session)
      Description copied from class: Expression
      If it is possible, return the negated expression. This is used to optimize NOT expressions: NOT ID>10 can be converted to ID<=10. Returns null if negating is not possible.
      Overrides:
      getNotIfPossible in class Expression
      Parameters:
      session - the session
      Returns:
      the negated expression, or null

    • mapColumns

      public void mapColumns(ColumnResolver resolver, int level, int state)
      Description copied from class: Expression
      Map the columns of the resolver to expression columns.
      Specified by:
      mapColumns in class Expression
      Parameters:
      resolver - the column resolver
      level - the subquery nesting level
      state - current state for nesting checks, initial value is Expression.MAP_INITIAL

    • setEvaluatable

      public void setEvaluatable(TableFilter tableFilter, boolean b)
      Description copied from class: Expression
      Tell the expression columns whether the table filter can return values now. This is used when optimizing the query.
      Specified by:
      setEvaluatable in class Expression
      Parameters:
      tableFilter - the table filter
      b - true if the table filter can return value

    • updateAggregate

      public void updateAggregate(SessionLocal session, int stage)
      Description copied from class: Expression
      Update an aggregate value. This method is called at statement execution time. It is usually called once for each row, but if the expression is used multiple times (for example in the column list, and as part of the HAVING expression) it is called multiple times - the row counter needs to be used to make sure the internal state is only updated once.
      Specified by:
      updateAggregate in class Expression
      Parameters:
      session - the session
      stage - select stage

    • isEverything

      public boolean isEverything(ExpressionVisitor visitor)
      Description copied from class: Expression
      Check if this expression and all sub-expressions can fulfill a criteria. If any part returns false, the result is false.
      Specified by:
      isEverything in class Expression
      Parameters:
      visitor - the visitor
      Returns:
      if the criteria can be fulfilled

    • getCost

      public int getCost()
      Description copied from class: Expression
      Estimate the cost to process the expression. Used when optimizing the query, to calculate the query plan with the lowest estimated cost.
      Specified by:
      getCost in class Expression
      Returns:
      the estimated cost

    • getSubexpressionCount

      public int getSubexpressionCount()
      Description copied from class: Expression
      Returns count of subexpressions.
      Overrides:
      getSubexpressionCount in class Expression
      Returns:
      count of subexpressions

    • getSubexpression

      public Expression getSubexpression(int index)
      Description copied from class: Expression
      Returns subexpression with specified index.
      Overrides:
      getSubexpression in class Expression
      Parameters:
      index - 0-based index
      Returns:
      subexpression with specified index, may be null