Informix Error -555: Cannot use a select or any of the database statements in a multi-query prepare.

Reasons / Common Causes

-555 fires when a PREPARE statement's text contains multiple statements separated by semicolons, and one of them is a SELECT, DATABASE, CREATE DATABASE, or CLOSE DATABASE statement — per the official guidance, these four statement types must always be prepared alone, never as part of a multi-statement batch.

1. A SELECT included in a semicolon-separated multi-statement prepare — per the official guidance, one of the four disallowed types in that context.
2. A DATABASE/CREATE DATABASE/CLOSE DATABASE statement bundled with others in the same prepared text, for the same reason.
3. Generic batch-preparation code that doesn't special-case these four statement types when assembling a multi-statement text.

Solutions / Resolution

1. Check the statement text string, and confirm whether multiple statements were actually intended, per the official guidance — sometimes an accidental semicolon merges what should have been separate PREPARE calls.
2. If multiple statements are genuinely intended, execute the SELECT/DATABASE/CREATE DATABASE/ CLOSE DATABASE statement on its own, per the official guidance, separate from any other statements in the batch.

Examples

The disallowed batch

EXEC SQL PREPARE multi_stmt FROM
  "SELECT * FROM orders WHERE order_id = ?; \
   UPDATE orders SET status = 'reviewed' WHERE order_id = ?";
-- -555: SELECT cannot be part of a multi-statement prepare

Split apart

EXEC SQL PREPARE select_stmt FROM "SELECT * FROM orders WHERE order_id = ?";
EXEC SQL PREPARE update_stmt FROM "UPDATE orders SET status = 'reviewed' WHERE order_id = ?";

Diagnostic Checks

1. Scan the prepared text for semicolons, and check whether any of the resulting individual statements is a SELECT, DATABASE, CREATE DATABASE, or CLOSE DATABASE — any of the four needs to be pulled out into its own prepare.

Related Errors / Related Topics

No closely related error codes are cross-referenced for -555 in this set yet.

Four specific statement types (SELECT, DATABASE, CREATE DATABASE, CLOSE DATABASE) can never be part of a multi-statement prepare — split them out into their own PREPARE.