Abstract: The present disclosure relates to a method for recovering a washing fluid, a device for recovering the washing fluid, and a washing fluid recovered by the method. The method includes preparing a positive electrode active material including a nickel-containing lithium composite oxide, adding a first washing fluid to the positive electrode active material to form a mixture, wherein the first washing fluid includes a coating raw material, and recovering the washing fluid from the mixture, wherein the washing fluid has a lithium concentration equal to or greater than about 3500 ppm.

Abstract: Provided are a method for preparing a lithium carbonate, a lithium carbonate prepared using the same, and a rechargeable lithium battery including a positive electrode active material prepared using the same, and more particularly, to a method for preparing a lithium carbonate, including mixing a lithium nickel-based composite oxide and a coating solution to form a first mixture where the coating solution includes a coating raw material, a precipitant, and a solvent, filtering the first mixture to recover a washing solution containing at least 1000 ppm of lithium, filtering the washing solution, mixing and heating the filtered washing solution and sodium carbonate to form a second mixture, and filtering, washing, and drying the second mixture, wherein the heating is performed at a temperature of about 50° C. to about 80° C.

Abstract: A method and system for managing database is disclosed, which is capable of simultaneously performing a data selection procedure and a data click-count update procedure when specific data is selected, the method comprising receiving and analyzing a query in which both a fetch request for a record included in a specific database table and an update request for at least one of columns included in the record are defined together; generating an execution plan to execute the analyzed query; and executing the execution plan by fetching the record and updating at least one of the columns according to the execution plan.

Abstract: A method and system for managing database is disclosed, which is capable of simultaneously performing a data selection procedure and a data click-count update procedure when specific data is selected, the method comprising receiving and analyzing a query in which both a fetch request for a record included in a specific database table and an update request for at least one of columns included in the record are defined together; generating an execution plan to execute the analyzed query; and executing the execution plan by fetching the record and updating at least one of the columns according to the execution plan.