SQL Reference

Chapter 2 | Supported standards 22
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.
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