IsJsonPredicate (H2 Database Engine 2.0.0 API)

java.lang.Object
- org.h2.expression.Expression
- - org.h2.expression.condition.IsJsonPredicate

所有已实现的接口:: HasSQL, Typed

public final class IsJsonPredicate
extends Expression

IS JSON predicate.

字段概要
- 从类继承的字段 org.h2.expression.Expression
  AUTO_PARENTHESES, MAP_IN_AGGREGATE, MAP_IN_WINDOW, MAP_INITIAL, WITH_PARENTHESES, WITHOUT_PARENTHESES
- 从接口继承的字段 org.h2.util.HasSQL
  ADD_PLAN_INFORMATION, DEFAULT_SQL_FLAGS, NO_CASTS, QUOTE_ONLY_WHEN_REQUIRED, REPLACE_LOBS_FOR_TRACE, TRACE_SQL_FLAGS

构造器概要

构造器
构造器和说明
`IsJsonPredicate(Expression left, boolean not, boolean whenOperand, boolean withUniqueKeys, JSONItemType itemType)`

方法概要

所有方法实例方法具体方法
限定符和类型	方法和说明
`int`	`getCost()` Estimate the cost to process the expression.
`Expression`	`getNotIfPossible(SessionLocal session)` If it is possible, return the negated expression.
`Expression`	`getSubexpression(int index)` Returns subexpression with specified index.
`int`	`getSubexpressionCount()` Returns count of subexpressions.
`TypeInfo`	`getType()` Returns the data type.
`StringBuilder`	`getUnenclosedSQL(StringBuilder builder, int sqlFlags)` Get the SQL statement of this expression.
`Value`	`getValue(SessionLocal session)` Return the resulting value for the current row.
`StringBuilder`	`getWhenSQL(StringBuilder builder, int sqlFlags)` Appends the SQL statement of this when operand to the specified builder.
`boolean`	`getWhenValue(SessionLocal session, Value left)` Return the resulting value of when operand for the current row.
`boolean`	`isEverything(ExpressionVisitor visitor)` Check if this expression and all sub-expressions can fulfill a criteria.
`boolean`	`isWhenConditionOperand()` Returns whether this expression is a right side of condition in a when operand.
`void`	`mapColumns(ColumnResolver resolver, int level, int state)` Map the columns of the resolver to expression columns.
`boolean`	`needParentheses()` Returns whether this expressions needs to be wrapped in parentheses when it is used as an argument of other expressions.
`Expression`	`optimize(SessionLocal session)` Try to optimize the expression.
`void`	`setEvaluatable(TableFilter tableFilter, boolean b)` Tell the expression columns whether the table filter can return values now.
`void`	`updateAggregate(SessionLocal session, int stage)` Update an aggregate value.

从类继承的方法 org.h2.expression.Expression
addFilterConditions, createIndexConditions, getAlias, getBooleanValue, getColumnName, getColumnNameForView, getEnclosedSQL, getNonAliasExpression, getNullable, getSchemaName, getSQL, getSQL, getSQL, getSQL, getTableAlias, getTableName, isConstant, isIdentity, isNullConstant, isValueSet, optimizeCondition, toString, writeExpressions, writeExpressions

从类继承的方法 java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

从接口继承的方法 org.h2.util.HasSQL
getTraceSQL

- 构造器详细资料
  - IsJsonPredicate
```
public IsJsonPredicate(Expression left,
                       boolean not,
                       boolean whenOperand,
                       boolean withUniqueKeys,
                       JSONItemType itemType)
```
- 方法详细资料
  - needParentheses
```
public boolean needParentheses()
```
    从类复制的说明: Expression
    
    Returns whether this expressions needs to be wrapped in parentheses when it is used as an argument of other expressions.
    
    覆盖:
    
    needParentheses 在类中 Expression
    
    返回:
    
    true if it is
  - getUnenclosedSQL
```
public StringBuilder getUnenclosedSQL(StringBuilder builder,
                                      int sqlFlags)
```
    从类复制的说明: 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.
    
    指定者:
    
    getUnenclosedSQL 在类中 Expression
    
    参数:
    
    builder - string builder
    
    sqlFlags - formatting flags
    
    返回:
    
    the specified string builder
  - getWhenSQL
```
public StringBuilder getWhenSQL(StringBuilder builder,
                                int sqlFlags)
```
    从类复制的说明: Expression
    
    Appends the SQL statement of this when operand to the specified builder.
    
    覆盖:
    
    getWhenSQL 在类中 Expression
    
    参数:
    
    builder - string builder
    
    sqlFlags - formatting flags
    
    返回:
    
    the specified string builder
  - optimize
```
public Expression optimize(SessionLocal session)
```
    从类复制的说明: Expression
    
    Try to optimize the expression.
    
    指定者:
    
    optimize 在类中 Expression
    
    参数:
    
    session - the session
    
    返回:
    
    the optimized expression
  - getValue
```
public Value getValue(SessionLocal session)
```
    从类复制的说明: Expression
    
    Return the resulting value for the current row.
    
    指定者:
    
    getValue 在类中 Expression
    
    参数:
    
    session - the session
    
    返回:
    
    the result
  - getWhenValue
```
public boolean getWhenValue(SessionLocal session,
                            Value left)
```
    从类复制的说明: Expression
    
    Return the resulting value of when operand for the current row.
    
    覆盖:
    
    getWhenValue 在类中 Expression
    
    参数:
    
    session - the session
    
    left - value on the left side
    
    返回:
    
    the result
  - isWhenConditionOperand
```
public boolean isWhenConditionOperand()
```
    从类复制的说明: Expression
    
    Returns whether this expression is a right side of condition in a when operand.
    
    覆盖:
    
    isWhenConditionOperand 在类中 Expression
    
    返回:
    
    true if it is, false otherwise
  - getNotIfPossible
```
public Expression getNotIfPossible(SessionLocal session)
```
    从类复制的说明: 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.
    
    覆盖:
    
    getNotIfPossible 在类中 Expression
    
    参数:
    
    session - the session
    
    返回:
    
    the negated expression, or null
  - setEvaluatable
```
public void setEvaluatable(TableFilter tableFilter,
                           boolean b)
```
    从类复制的说明: Expression
    
    Tell the expression columns whether the table filter can return values now. This is used when optimizing the query.
    
    指定者:
    
    setEvaluatable 在类中 Expression
    
    参数:
    
    tableFilter - the table filter
    
    b - true if the table filter can return value
  - updateAggregate
```
public void updateAggregate(SessionLocal session,
                            int stage)
```
    从类复制的说明: 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.
    
    指定者:
    
    updateAggregate 在类中 Expression
    
    参数:
    
    session - the session
    
    stage - select stage
  - mapColumns
```
public void mapColumns(ColumnResolver resolver,
                       int level,
                       int state)
```
    从类复制的说明: Expression
    
    Map the columns of the resolver to expression columns.
    
    指定者:
    
    mapColumns 在类中 Expression
    
    参数:
    
    resolver - the column resolver
    
    level - the subquery nesting level
    
    state - current state for nesting checks, initial value is Expression.MAP_INITIAL
  - isEverything
```
public boolean isEverything(ExpressionVisitor visitor)
```
    从类复制的说明: Expression
    
    Check if this expression and all sub-expressions can fulfill a criteria. If any part returns false, the result is false.
    
    指定者:
    
    isEverything 在类中 Expression
    
    参数:
    
    visitor - the visitor
    
    返回:
    
    if the criteria can be fulfilled
  - getCost
```
public int getCost()
```
    从类复制的说明: Expression
    
    Estimate the cost to process the expression. Used when optimizing the query, to calculate the query plan with the lowest estimated cost.
    
    指定者:
    
    getCost 在类中 Expression
    
    返回:
    
    the estimated cost
  - getSubexpressionCount
```
public int getSubexpressionCount()
```
    从类复制的说明: Expression
    
    Returns count of subexpressions.
    
    覆盖:
    
    getSubexpressionCount 在类中 Expression
    
    返回:
    
    count of subexpressions
  - getSubexpression
```
public Expression getSubexpression(int index)
```
    从类复制的说明: Expression
    
    Returns subexpression with specified index.
    
    覆盖:
    
    getSubexpression 在类中 Expression
    
    参数:
    
    index - 0-based index
    
    返回:
    
    subexpression with specified index, may be null
  - getType
```
public TypeInfo getType()
```
    从类复制的说明: Expression
    
    Returns the data type. The data type may be unknown before the optimization phase.
    
    指定者:
    
    getType 在接口中 Typed
    
    指定者:
    
    getType 在类中 Expression
    
    返回:
    
    the data type

类 IsJsonPredicate

字段概要

从类继承的字段 org.h2.expression.Expression

从接口继承的字段 org.h2.util.HasSQL

构造器概要

方法概要

从类继承的方法 org.h2.expression.Expression

从类继承的方法 java.lang.Object

从接口继承的方法 org.h2.util.HasSQL

构造器详细资料

IsJsonPredicate

方法详细资料

needParentheses

getUnenclosedSQL

getWhenSQL

optimize

getValue

getWhenValue

isWhenConditionOperand

getNotIfPossible

setEvaluatable

updateAggregate

mapColumns

isEverything

getCost

getSubexpressionCount

getSubexpression

getType