public enum Mutation.Op extends Enum<Mutation.Op>
Enumerates the types of mutation that can be applied.
Deletes rows from a table. Succeeds whether or not the named rows were present.
Inserts a new row in a table. If the row already exists, the write or transaction fails with ErrorCode#ALREADY_EXISTS. When inserting a row, all NOT NULL columns in the table must be given a value.
Like #INSERT, except that if the row already exists, then its column values are overwritten with the ones provided. All NOT NUll columns in the table must be give a value and this holds true even when the row already exists and will actually be updated. Values for all NULL columns not explicitly written are preserved.
Like #INSERT, except that if the row already exists, it is deleted, and the column
values provided are inserted instead. Unlike #INSERT_OR_UPDATE, this means any values
not explicitly written become
Updates an existing row in a table. If the row does not already exist, the transaction fails with error ErrorCode#NOT_FOUND.