Updating mysql tables from external file Chat with girl without membership
See Behavior Differences Between SQL*Loader and External Tables for more information about how load behavior differs between SQL*Loader and external tables.To use the external tables feature, you must have some knowledge of the file format and record format of the datafiles on your platform if the access driver is used and the datafiles are in text format.This difference has the following implications: The access driver does not allow you to specify a complete specification for files.This is because the server may have access to files that you do not, and allowing you to read this data would affect security.For example, if a source table has a access driver attempts to divide large datafiles into chunks that can be processed separately.The following file, record, and data characteristics make it impossible for a file to be processed in parallel: clause should specify as many files as there are degrees of parallelism.
For example, assume a table in the database is defined as follows: CREATE TABLE roster_data ( student_no CHAR(5), name CHAR(20), grade CHAR(2)) ORGANIZATION EXTERNAL (TYPE ORACLE_LOADER DEFAULT DIRECTORY ext_tab_dir ACCESS PARAMETERS (FIELDS TERMINATED BY ',') LOCATION ('info.dat')); Any conversion errors that occur between the datafile and the external table cause the row with the error to be ignored.
You must also know enough about SQL to be able to create an external table and perform queries against it.
This chapter discusses the following topics: CREATE TABLE emp_load 2 (employee_number CHAR(5), 3 employee_dob CHAR(20), 4 employee_last_name CHAR(20), 5 employee_first_name CHAR(15), 6 employee_middle_name CHAR(15), 7 employee_hire_date DATE) 8 ORGANIZATION EXTERNAL 9 (TYPE ORACLE_LOADER 10 DEFAULT DIRECTORY def_dir1 11 ACCESS PARAMETERS 12 (RECORDS DELIMITED BY NEWLINE 13 FIELDS (employee_number CHAR(2), 14 employee_dob CHAR(20), 15 employee_last_name CHAR(18), 16 employee_first_name CHAR(11), 17 employee_middle_name CHAR(11), 18 employee_hire_date CHAR(10) date_format DATE mask "mm/dd/yyyy" 19 ) 20 ) 21 LOCATION ('info.dat') 22 ); Table created.
If a conversion error occurs, then the datafile may not contain all the rows that were processed up to that point and the datafile will not be readable.
To avoid problems with conversion errors causing the operation to fail, the datatype of the column in the external table should match the datatype of the column in the database.