CRUD and row mapping

Raw-table and entity paths

insert, update, and delete provide both a thin table-oriented SQL DSL and Spring Data entity operations. Use the raw-table path when the adapter owns the SQL shape, and the entity path when mapping metadata and the domain type drive the operation.

val id = client
    .insert()
    .into("users", "user_id")
    .value("username", "nick")
    .value("password", "pass")
    .value("name", "Nick")
    .nullValue("description", String::class.java)
    .awaitOne()

Use awaitOneLong() for generated keys larger than Int. The README’s sqlInsert and awaitGeneratedKey do not exist in 1.11.0 source and are not used here.

Make update and delete scope explicit

val changed = client
    .update()
    .table("users")
    .set("active", false)
    .matching("username = :username", mapOf("username" to "nick"))
    .fetch()
    .awaitRowsUpdated()

Omitting matching() can target every row. Validate condition presence unless a full-table update or delete is intentional.

Identifier validation boundary

Raw CRUD accepts table and column identifiers that begin with a letter or underscore and contain only letters, digits, underscores, and dots. This blocks value injection through identifier positions. It does not parse the raw where string, order expression, or arbitrary SQL. Bind values as parameters and build SQL fragments only from trusted code.

Typed rows and PostgreSQL JSON

R2dbcClient.execute<T> delegates to MappingR2dbcConverter. Align simple projection aliases with property names and register Spring converters for richer rules. ReadableSupport adds named and indexed accessors for numbers, strings, dates, times, byte arrays, and UUIDs, including nullable variants.

JsonToMapConverter and MapToJsonConverter bridge the PostgreSQL driver’s Json and Map<String, Any?> through Jackson3. Both integrations are optional runtime capabilities. Malformed JSON and serialization failures propagate as ConversionFailedException with the Jackson cause rather than becoming empty values.

Sources and tests

• Insert.kt
• Update.kt
• Delete.kt
• ReadableSupport.kt
• PostgresJsonConvertersTest.kt
• InsertTest.kt
• UpdateTest.kt

Next chapter

Continue to Dynamic queries when optional predicates begin to accumulate.