While both classes share the same, thin client-side API,JsonBstores the data in a decomposed, binary format, whereasJsonstores an exact copy of the RFC 7159 text.
This means thatJsonBis slower to input, but faster to process as it avoids reparsing. Therefore, applications that utilize the structured state of a JSON value should preferJsonB.
It also means that theJsonBstored representation does NOT preserve:
white space,
the order of object keys, or
duplicate object keys.
Note:JsonBis only applicable to PostgreSQL databases (i.e., those created usingDatabaseDialect::POSTGRESQL).
Constructors
JsonB(JsonB const &)
Regular value type, supporting copy, assign, move.
Parameter
Name
Description
JsonB const &
JsonB(JsonB &&)
Regular value type, supporting copy, assign, move.
Parameter
Name
Description
JsonB &&
JsonB()
A null value.
JsonB(std::string)
Construction from a JSON-formatted string.
Note that there is no check here that the argument string is indeed well-formatted. Error detection will be delayed until the value is passed to Spanner.
Parameter
Name
Description
s
std::string
Operators
operator=(JsonB const &)
Regular value type, supporting copy, assign, move.
Parameter
Name
Description
JsonB const &
Returns
Type
Description
JsonB &
operator=(JsonB &&)
Regular value type, supporting copy, assign, move.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-09-04 UTC."],[[["\u003cp\u003eThe \u003ccode\u003eJsonB\u003c/code\u003e class in the Spanner C++ library is designed for storing JSON data in a decomposed, binary format, which optimizes processing speed over the \u003ccode\u003eJson\u003c/code\u003e class.\u003c/p\u003e\n"],["\u003cp\u003eWhile \u003ccode\u003eJsonB\u003c/code\u003e provides faster processing, it is slower to input data compared to \u003ccode\u003eJson\u003c/code\u003e because it avoids reparsing, which makes \u003ccode\u003eJsonB\u003c/code\u003e more suitable for applications requiring structured state access of JSON values.\u003c/p\u003e\n"],["\u003cp\u003e\u003ccode\u003eJsonB\u003c/code\u003e does not preserve white space, the order of object keys, or duplicate object keys in its stored representation.\u003c/p\u003e\n"],["\u003cp\u003eThe class \u003ccode\u003eJsonB\u003c/code\u003e is only applicable to PostgreSQL databases.\u003c/p\u003e\n"],["\u003cp\u003eThe class \u003ccode\u003eJsonB\u003c/code\u003e supports copy, assign and move operations.\u003c/p\u003e\n"]]],[],null,["# Class JsonB (2.18.0)\n\nVersion 2.18.0keyboard_arrow_down\n\n- [2.42.0-rc (latest)](/cpp/docs/reference/spanner/latest/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.41.0](/cpp/docs/reference/spanner/2.41.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.40.0](/cpp/docs/reference/spanner/2.40.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.39.0](/cpp/docs/reference/spanner/2.39.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.38.0](/cpp/docs/reference/spanner/2.38.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.37.0](/cpp/docs/reference/spanner/2.37.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.36.0](/cpp/docs/reference/spanner/2.36.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.35.0](/cpp/docs/reference/spanner/2.35.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.34.0](/cpp/docs/reference/spanner/2.34.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.33.0](/cpp/docs/reference/spanner/2.33.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.32.0](/cpp/docs/reference/spanner/2.32.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.31.0](/cpp/docs/reference/spanner/2.31.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.30.0](/cpp/docs/reference/spanner/2.30.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.29.0](/cpp/docs/reference/spanner/2.29.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.28.0](/cpp/docs/reference/spanner/2.28.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.27.0](/cpp/docs/reference/spanner/2.27.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.26.0](/cpp/docs/reference/spanner/2.26.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.25.1](/cpp/docs/reference/spanner/2.25.1/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.24.0](/cpp/docs/reference/spanner/2.24.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.23.0](/cpp/docs/reference/spanner/2.23.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.22.1](/cpp/docs/reference/spanner/2.22.1/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.21.0](/cpp/docs/reference/spanner/2.21.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.20.0](/cpp/docs/reference/spanner/2.20.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.19.0](/cpp/docs/reference/spanner/2.19.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.18.0](/cpp/docs/reference/spanner/2.18.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.17.0](/cpp/docs/reference/spanner/2.17.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.16.0](/cpp/docs/reference/spanner/2.16.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.15.1](/cpp/docs/reference/spanner/2.15.1/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.14.0](/cpp/docs/reference/spanner/2.14.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.13.0](/cpp/docs/reference/spanner/2.13.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.12.0](/cpp/docs/reference/spanner/2.12.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB)\n- [2.11.0](/cpp/docs/reference/spanner/2.11.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB) \n[`JsonB`](/cpp/docs/reference/spanner/2.18.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB) is a variant of [`Json`](/cpp/docs/reference/spanner/2.18.0/classgoogle_1_1cloud_1_1spanner_1_1Json) (see above). \nWhile both classes share the same, thin client-side API, [`JsonB`](/cpp/docs/reference/spanner/2.18.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB) stores the data in a decomposed, binary format, whereas [`Json`](/cpp/docs/reference/spanner/2.18.0/classgoogle_1_1cloud_1_1spanner_1_1Json) stores an exact copy of the RFC 7159 text.\n\nThis means that [`JsonB`](/cpp/docs/reference/spanner/2.18.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB) is slower to input, but faster to process as it avoids reparsing. Therefore, applications that utilize the structured state of a JSON value should prefer [`JsonB`](/cpp/docs/reference/spanner/2.18.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB).\n\nIt also means that the [`JsonB`](/cpp/docs/reference/spanner/2.18.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB) stored representation does NOT preserve:\n\n- white space,\n- the order of object keys, or\n- duplicate object keys.\n\nNote: [`JsonB`](/cpp/docs/reference/spanner/2.18.0/classgoogle_1_1cloud_1_1spanner_1_1JsonB) is only applicable to PostgreSQL databases (i.e., those created using `DatabaseDialect::POSTGRESQL`).\n\nConstructors\n------------\n\n### JsonB(JsonB const \\&)\n\nRegular value type, supporting copy, assign, move.\n\n### JsonB(JsonB \\&\\&)\n\nRegular value type, supporting copy, assign, move.\n\n### JsonB()\n\nA null value.\n\n### JsonB(std::string)\n\nConstruction from a JSON-formatted string. \nNote that there is no check here that the argument string is indeed well-formatted. Error detection will be delayed until the value is passed to Spanner.\n\nOperators\n---------\n\n### operator=(JsonB const \\&)\n\nRegular value type, supporting copy, assign, move.\n\n### operator=(JsonB \\&\\&)\n\nRegular value type, supporting copy, assign, move.\n\n### operator std::string() const \\&\n\nConversion to a JSON-formatted string.\n\n### operator std::string() \\&\\&\n\nConversion to a JSON-formatted string."]]
