$bitsAllSet

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$bitsAllSet

$bitsAllSet matches documents where all of the bit positions given by the query are set (i.e. 1) in field.匹配字段中设置了查询给出的所有位位置（即1）的文档。

{ <field>: { $bitsAllSet: <numeric bitmask> } }
{ <field>: { $bitsAllSet: < BinData bitmask> } }
{ <field>: { $bitsAllSet: [ <position1>, <position2>, ... ] } }

The field value must be either numeric or a BinData instance. field值必须是数字或BinData实例。Otherwise, $bitsAllSet will not match the current document.否则，$bitsAllSet将与当前文档不匹配。

Numeric Bitmask
You can provide a numeric bitmask to be matched against the operand field. 您可以提供要与操作数字段匹配的数字位掩码。It must be representable as a non-negative 32-bit signed integer. 它必须可以表示为非负的32位有符号整数。Otherwise, $bitsAllSet will return an error.否则，$bitsAllSet将返回错误。
BinData Bitmask
You can also use an arbitrarily large BinData instance as a bitmask.您还可以使用任意大的BinData实例作为位掩码。
Position List职位列表
If querying a list of bit positions, each <position> must be a non-negative integer. 如果查询位位置列表，则每个<position>必须是非负整数。Bit positions start at 0 from the least significant bit. 位位置从最低有效位的0开始。For example, the decimal number 254 would have the following bit positions:例如，十进制数254将具有以下位位置：
Bit Value11111110
Position76543210

Behavior行为

Indexes索引

Queries cannot use indexes for the $bitsAllSet portion of a query, although the other portions of a query can use indexes, if applicable.查询不能对查询的$bitsAllSet部分使用索引，尽管查询的其他部分可以使用索引（如果适用）。

Floating Point Values浮点值

$bitsAllSet will not match numerical values that cannot be represented as a signed 64-bit integer. 将与不能表示为带符号64位整数的数值不匹配。This can be the case if a value is either too large or too small to fit in a signed 64-bit integer, or if it has a fractional component.如果一个值太大或太小而无法放入带符号的64位整数，或者它有一个分数分量，则会出现这种情况。

Sign Extension标志扩展名

Numbers are sign extended. 数字是符号扩展的。For example, $bitsAllSet considers bit position 200 to be set for the negative number -5, but bit position 200 to be clear for the positive number +5.例如，$bitsAllSet认为要为负数-5设置位位置200，但要为正数+5清除位位置200。

In contrast, BinData instances are zero-extended. 相反，BinData实例是零扩展的。For example, given the following document:例如，给定以下文档：

db.collection.save({ x: BinData(0, "ww=="), binaryValueofA: "11000011" })

$bitsAllSet will consider all bits outside of x to be clear.将认为x以外的所有位都是清除的。

Examples示例

The following examples will use a collection with the following documents:以下示例将使用包含以下文档的集合：

db.collection.save({ _id: 1, a: 54, binaryValueofA: "00110110" })
db.collection.save({ _id: 2, a: 20, binaryValueofA: "00010100" })
db.collection.save({ _id: 3, a: 20.0, binaryValueofA: "00010100" })
db.collection.save({ _id: 4, a: BinData(0, "Zg=="), binaryValueofA: "01100110" })

Bit Position Array位位置数组

The following query uses the $bitsAllSet operator to test whether field a has bits set at position 1 and position 5, where the least significant bit is position 0.以下查询使用$bitsAllSet运算符测试字段a是否在位置1和位置5设置了位，其中最低有效位为位置0。

db.collection.find( { a: { $bitsAllSet: [ 1, 5 ] } } )

The query matches the following documents:查询匹配以下文档：

{ "_id" : 1, "a" : 54, "binaryValueofA" : "00110110" }
{ "_id" : 4, "a" : BinData(0,"Zg=="), "binaryValueofA" : "01100110" }

Integer Bitmask整数位掩码

The following query uses the $bitsAllSet operator to test whether field a has bits set at positions 1, 4, and 5(the binary representation of the bitmask 50 is 00110010).以下查询使用$bitsAllSet运算符测试字段a是否在位置1、4和5处设置了位（位掩码50的二进制表示形式为00110010）。

db.collection.find( { a: { $bitsAllSet: 50 } } )

The query matches the following document:查询匹配以下文档：

{ "_id" : 1, "a" : 54, "binaryValueofA" : "00110110" }

BinData BitmaskBinData位掩码

The following query uses the $bitsAllSet operator to test whether field a has bits set at positions 4 and 5(the binary representation of BinData(0, "MC==") is 00110000).以下查询使用$bitsAllSet运算符测试字段a是否在位置4和5处设置了位（BinData(0, "MC==")的二进制表示形式为00110000）。

db.collection.find( { a: { $bitsAllSet: BinData(0, "MC==") } } )

The query matches the following document:查询匹配以下文档：

{ _id: 1, a: 54, binaryValueofA: "00110110" }
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