---
title: "PREPARE"
id: ecpg-sql-prepare
pg_version: "20devel"
---

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# PREPARE — prepare a statement for execution

## Synopsis

```
PREPARE prepared_name FROM string
```

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## Description

`PREPARE` prepares a statement dynamically specified as a string for execution. This is different from the direct SQL statement [PREPARE](sql-prepare.md), which can also be used in embedded programs. The [EXECUTE](sql-execute.md) command is used to execute either kind of prepared statement. 

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## Parameters

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**`prepared_name`**

 An identifier for the prepared query. <a id="ecpg-sql-prepare-string"></a>

**`string`**

 A literal string or a host variable containing a preparable SQL statement, one of SELECT, INSERT, UPDATE, or DELETE. Use question marks (`?`) for parameter values to be supplied at execution. <a id="id-1.7.5.20.13.5"></a>

## Notes

In typical usage, the `string` is a host variable reference to a string containing a dynamically-constructed SQL statement. The case of a literal string is not very useful; you might as well just write a direct SQL `PREPARE` statement. 

If you do use a literal string, keep in mind that any double quotes you might wish to include in the SQL statement must be written as octal escapes (`\042`) not the usual C idiom `\"`. This is because the string is inside an `EXEC SQL` section, so the ECPG lexer parses it according to SQL rules not C rules. Any embedded backslashes will later be handled according to C rules; but `\"` causes an immediate syntax error because it is seen as ending the literal. 

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## Examples


char *stmt = "SELECT * FROM test1 WHERE a = ? AND b = ?";

EXEC SQL ALLOCATE DESCRIPTOR outdesc;
EXEC SQL PREPARE foo FROM :stmt;

EXEC SQL EXECUTE foo USING SQL DESCRIPTOR indesc INTO SQL DESCRIPTOR outdesc;
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## Compatibility

`PREPARE` is specified in the SQL standard. 

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## See Also

[EXECUTE](sql-execute.md)