feat: add missing methods

[TheSench]

This PR adds some missing methods to flesh out interfaces and make DB and Tx have more of a shared interface.

This opens up the possibility of creating a common interface that represents either one so that functions can be written that execute queries without needing to know if they're being run within a transaction or not.

• TODO: Add unit tests.
  I wasn't sure how the tests were organized for this project. If there's a specific test function you'd like them added to (or a new one), let me know.

📌 Long-term (future PR), I'd like to create an interface (or a few) that represent the remaining shared query-related methods, and then one interface that represents either a DB or Tx. These are the additional methods not represented in another interface right now:

• Get(dest interface{}, query string, args ...interface{}) error
• GetContext(ctx context.Context, dest interface{}, query string, args ...interface{}) error
• MustExec(query string, args ...interface{}) sql.Result
• MustExecContext(ctx context.Context, query string, args ...interface{}) sql.Result
• NamedExec(query string, arg interface{}) (sql.Result, error)
• NamedExecContext(ctx context.Context, query string, arg interface{}) (sql.Result, error)
• NamedQuery(query string, arg interface{}) (*sqlx.Rows, error)
• NamedQueryContext(ctx context.Context, query string, arg interface{}) (*sqlx.Rows, error)
• PrepareNamed(query string) (*sqlx.NamedStmt, error)
• PrepareNamedContext(ctx context.Context, query string) (*sqlx.NamedStmt, error)
• Preparex(query string) (*sqlx.Stmt, error)
• PreparexContext(ctx context.Context, query string) (*sqlx.Stmt, error)
• Select(dest interface{}, query string, args ...interface{}) error
• SelectContext(ctx context.Context, dest interface{}, query string, args ...interface{}) error

[TheSench]

Implementation notes:

[TheSench]

Note

Adding a missing method to this interface.

We have Query/Queryx, and QueryRowx, but this method was missing.

[TheSench]

Note

Adding a missing method to this interface.

We have QueryContext/QueryxContext, and QueryRowxContext, but this method was missing.

[TheSench]

Note

This method exists on DB, but was missing from Tx.

This is the only query-related method I found that is needed to allow these two types to be used interchangeably.

[mrj0]

I ran into this too! Totally agree, there should be a common interface. I ended up making one for the subset of methods that we use, but it can be easier.

[syrm]

I need this too

[slashformotion]

LGTM, we need this merged ASAP please.

Would be great to get this moving !