ODBC and JDBC Guide

Chapter 7
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Supported standards 45
Examples
Note SET DEFAULT and DROP DEFAULT do not affect existing rows in the table, but change the default
value for rows that are subsequently added to the table.
CREATE INDEX statement
Use the CREATE INDEX statement to speed searches in your database file. The format of the CREATE
INDEX statement is:
CREATE INDEX ON table_name.column_name
CREATE INDEX ON table_name (column_name)
CREATE INDEX is supported for a single column (multi-column indexes are not supported). Indexes are
not allowed on columns that correspond to container field types, summary fields, fields that have the global
storage option, or unstored calculation fields in a FileMaker database file.
Creating an index for a text column automatically selects the Storage Option of Minimal in Indexing for the
corresponding field in the FileMaker database file. Creating an index for a non-text column (or a column
formatted as Japanese text) automatically selects the Storage Option of All in
Indexing for the corresponding
field in the FileMaker database file.
Creating an index for any column automatically selects the Storage Option of Automatically create indexes
as needed in Indexing for the corresponding field in the FileMaker database file.
FileMaker automatically creates indexes as needed. Using CREATE INDEX causes the index to be built
immediately rather than on demand.
Example
CREATE INDEX ON Salespeople.Salesperson_ID
DROP INDEX statement
Use the DROP INDEX statement to remove an index from a database file. The format of the DROP INDEX
statement is:
DROP INDEX ON table_name.column_name
DROP INDEX ON table_name (column_name)
Remove an index when your database file is too large, or you don’t often use a field in queries.
If your queries are experiencing poor performance, and you’re working with an extremely large FileMaker
database file with many indexed text fields, consider dropping the indexes from some fields. Also consider
dropping the indexes from fields that you rarely use in SELECT statements.
Dropping an index for any column automatically selects the Storage Option of None and clears
Automatically create indexes as needed in Indexing for the corresponding field in the FileMaker database
file.
To Sample SQL
add columns
ALTER TABLE Salespeople ADD C1 VARCHAR
remove columns
ALTER TABLE Salespeople DROP C1
set the default value for a
column
ALTER TABLE Salespeople ALTER Company SET DEFAULT ‘FileMaker’
remove the default value for
a column
ALTER TABLE Salespeople ALTER Company DROP DEFAULT