Sybase Adaptive Server IQ 12.4.2, Руководство по администрированию и эксплуатации

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C H A P T E R 5
Moving Data In and Out of
Databases
About this chapter This chapter describes several methods of moving data into and out of
your database, and explains when you should use each of them. It also
discusses conversion issues for data inserted from other types of
databases.
Import and export overview
Adaptive Server IQ lets you import data from flat files, or directly from
database tables. You can also enter specified values directly into the
database. Export of data to other formats, such as spreadsheet program
formats, is available from the DBISQL utility.
An Adaptive Server IQ table is a logical table; it does not contain data. All
the information needed to resolve queries, including data, is contained in
the Adaptive Server IQ indexes. When you insert data into the columns in
an IQ table, you are not actually adding data to the columns in the table,
but rather to the column indexes. You build indexes by inserting data on a
table-by-table basis.
Import and export methods
Adaptive Server IQ offers you a choice of methods for adding, changing,
or deleting data.
• For efficient bulk loading of tables from flat files, use the SQL
statement
LOAD TABLE
.
• To insert specified values into a table row by row, use the SQL
statement
INSERT
with the
VALUES
option.
• To insert rows selected from a database, use the SQL statement
INSERT
with a
SELECT
statement clause.