While both classes share the same, thin client-side API, JsonB stores the data in a decomposed, binary format, whereas Json stores an exact copy of the RFC 7159 text.
This means that JsonB 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.
It also means that the JsonB stored representation does NOT preserve:
white space,
the order of object keys, or
duplicate object keys.
Note: JsonB is only applicable to PostgreSQL databases (i.e., those created using DatabaseDialect::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"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-22 UTC."],[[["\u003cp\u003eThe webpage details the \u003ccode\u003eJsonB\u003c/code\u003e class within the Google Cloud Spanner C++ library, specifically in relation to its numerous versions, with version 2.37.0-rc being the latest.\u003c/p\u003e\n"],["\u003cp\u003e\u003ccode\u003eJsonB\u003c/code\u003e is a variant of the \u003ccode\u003eJson\u003c/code\u003e class, utilizing a binary format for data storage which is more efficient for processing but slower for input.\u003c/p\u003e\n"],["\u003cp\u003eUnlike \u003ccode\u003eJson\u003c/code\u003e, \u003ccode\u003eJsonB\u003c/code\u003e does not preserve white space, object key order, or duplicate object keys in its stored representation.\u003c/p\u003e\n"],["\u003cp\u003e\u003ccode\u003eJsonB\u003c/code\u003e is tailored for PostgreSQL databases and is preferred for applications that work with the structured state of JSON values because it avoids reparsing.\u003c/p\u003e\n"],["\u003cp\u003e\u003ccode\u003eJsonB\u003c/code\u003e class offers multiple constructors and operators, including support for copy, assignment, move operations, null values, construction from JSON-formatted strings, and conversion to a JSON-formatted string.\u003c/p\u003e\n"]]],[],null,[]]