Decouple SQLTx and SQLDatabase.

builder.go

db.go

errors.go

internal/sqladapter/database.go

internal/sqladapter/result.go

internal/sqladapter/testing/adapter.go.tpl

internal/sqladapter/testing/adapter_benchmark.go.tpl

internal/sqladapter/tx.go

postgresql/connection.go

postgresql/database.go

postgresql/postgresql.go

postgresql/template_test.go

sqlbuilder/builder.go

wrapper.go