Transfer of table instances between databases

• US 7,885,927 B2
• Filed: 07/18/2008
• Issued: 02/08/2011
• Est. Priority Date: 01/31/2005
• Status: Expired due to Fees

• Current Assignee: Hulu LLC (The Walt Disney Company)
• Original Assignee: International Business Machines Corporation
• Inventors: Bangel, Matthew J., Martin, James A. Jr.
• Primary Examiner(s): Cottingham; John R.
• Assistant Examiner(s): Badawi; Sherief
• Application Number:
  US12/175,832
• Publication Number:
  US 20080275927A1
• Time in Patent Office: 935 Days
• Field of Search: 707/635, 707/634, 707/626, 707/809, 707/610, 707/620, 707/655
• US Class Current: 707/634
• CPC Class Codes: G06F 16/20 of structured data, e.g. relational data
• CPC Class Codes: Y10S 707/99942 Manipulating data structure, e.g. compression, compaction, compilation
• CPC Class Codes: Y10S 707/99952 Coherency, e.g. same view to multiple users

Abstract

A system and computer program product for transferring N table instances X₁, X₂, . . . , X_N of a table T from a source database S to destination databases D₁, D₂, . . . , D_N, respectively. The method is implemented by executing a computer code by a processor of a computer system. N is at least 1. For I=1, 2, . . . , N the method includes: determining whether the table T has been defined for destination database D_I, and if it is determined that the table T has not been defined for the destination database D_I then defining the table T for the destination database D_I; and transferring the instance X_I of the N table instances from the source database S into the defined table T of the destination database D_I.

Claims

1. A computer system comprising a processor and a computer readable memory unit coupled to the processor, said memory unit containing computer code that when executed by the processor implement a method for transferring table instances X₁, X₂, . . . , X_N of a table T from a source database S to destination databases D₁, D₂, . . . , D_N, respectively, said N being at least 1, said method comprising for I=1, 2, . . . , N:

determining whether the table T has been defined for destination database D_I, and if said determining determines that the table T has not been defined for the destination database D_I then defining the table T for the destination database D_I; and

transferring the instance X_I of the N table instances from the source database S into the defined table T of the destination database D_I,

wherein the method further comprises prior to said determining whether the table T has been defined for destination database D_I and prior to said transferring the instance X_I;

specifying an instance configuration pertaining to the table instance X_I, wherein the instance configuration consists of an instance variable of the table T in combination with a value of the instance variable, and wherein the instance variable defines a set of rows of the table T pertaining to the table instance X_I;

generating a first database query statement from said instance configuration pertaining to the table instance X_I, wherein the first database query statement is configured to return the table instance X_I from the table T in the source database S in response to being performed; and

performing a first source database query on the source database S using the generated first database query statement, resulting in returning the table instance X_I from the table T in the source database,

wherein said determining whether the table T has been defined for destination database D_I comprises;

generating a destination database query statement from said instance configuration pertaining to the table instance X_I, wherein the destination database query statement is configured to return data from the table T in the destination database D_I in response to being performed; and

performing a destination database query on the destination database D_I using the generated second database query statement, resulting in returning data from the table T in the destination database D_I if the table T has been defined for destination database D_I or in not returning data from the table T in the destination database D_I if the table T has not been defined for destination database D_I,

wherein said performing the destination database query on the destination database D_I results in not returning data from the table T in the destination database D_I, wherein said defining the table T for the destination database D_I comprises;

creating schema and determining metadata associated with the schema, wherein said schema and associated metadata define the table T in the destination database D_I,

wherein said determining metadata comprises performing a second database query on the source database S, resulting in returning the metadata from the source database S.

2. The computer system of claim 1, wherein said transferring comprises:

selecting the instance X_I from the source database S; and

inserting the selected instance X_I into the defined table T of the destination database D_I,

wherein said determining and said selecting are implemented by a single database query statement.

3. A computer program product, comprising a computer usable medium having a computer readable program code embodied therein, said computer readable program code comprising an algorithm that when executed by a processor of a computer system implement a method for transferring table instances X₁, X₂, . . . , X_N of a table T from a source database S to destination databases D₁, D₂, . . . , D_N, respectively, said N being at least 1, said method comprising:

determining whether the table T has been defined for destination database D_I, and if said determining determines that the table T has not been defined for the destination database D_I then defining the table T for the destination database D_I; and

transferring the instance X_I of the N table instances from the source database S into the defined table T of the destination database D_I,

wherein the method further comprises prior to said determining whether the table T has been defined for destination database D_I and prior to said transferring the instance X_I;

specifying an instance configuration pertaining to the table instance X_I, wherein the instance configuration consists of an instance variable of the table T in combination with a value of the instance variable, and wherein the instance variable defines a set of rows of the table T pertaining to the table instance X_I;

generating a first database query statement from said instance configuration pertaining to the table instance X_I, wherein the first database query statement is configured to return the table instance X_I from the table T in the source database S in response to being performed; and

performing a first source database query on the source database S using the generated first database query statement, resulting in returning the table instance X_I from the table T in the source database,

wherein said determining whether the table T has been defined for destination database D_I comprises;

generating a destination database query statement from said instance configuration pertaining to the table instance X_I, wherein the destination database query statement is configured to return data from the table T in the destination database D_I in response to being performed; and

performing a destination database query on the destination database D_I using the generated second database query statement, resulting in returning data from the table T in the destination database D_I if the table T has been defined for destination database D_I or in not returning data from the table T in the destination database D_I if the table T has not been defined for destination database D_I,

wherein said performing the destination database query on the destination database D_I results in not returning data from the table T in the destination database D_I, wherein said defining the table T for the destination database D_I comprises;

creating schema and determining metadata associated with the schema, wherein said schema and associated metadata define the table T in the destination database D_I,

wherein said determining metadata comprises performing a second database query on the source database S, resulting in returning the metadata from the source database S.

4. The computer program product of claim 3, wherein said transferring comprises:

selecting the instance X_I from the source database S; and

inserting the selected instance X_I into the defined table T of the destination database D_I,

wherein said determining and said selecting are implemented by a single database query statement.