PHP developers sometimes need to export PostgreSQL table rows to an array of COPY text lines. This comes up when preparing data, displaying results, or integrating information with other services.
The Pdo\\Pgsql::copyToArray() operation handles this particular task. The following examples show its result, its limitations, and a practical way to apply it.
What Is Pdo\\Pgsql::copyToArray() in PHP?
Export PostgreSQL table rows to an array of COPY text lines.
Its syntax is:
Pdo\Pgsql::copyToArray(string $tableName, string $separator = "\t", string $nullAs = "\\N", ?string $fields = null): array
The syntax shows the expected parameters and return type. Arguments marked with an ampersand are passed by reference and may be modified. Optional parameters control additional behavior; values must match the declared types.
Important: Rows are raw PostgreSQL COPY text records, not decoded associative arrays. Native Pdo\\Pgsql requires PHP 8.4+ and a PostgreSQL connection.
Parameters:
$tableName— A named input or configuration argument; use the declared type and optional default shown above.$separator— A named input or configuration argument; use the declared type and optional default shown above.$nullAs— A named input or configuration argument; use the declared type and optional default shown above.$fields— A named input or configuration argument; use the declared type and optional default shown above.
Example 1: Basic Usage
This first example uses a small input to demonstrate the main result of Pdo\\Pgsql::copyToArray().
<?php
$database = new Pdo\Pgsql("pgsql:host=localhost;dbname=demo", "app", "secret"); $rows = $database->copyToArray("people"); print_r($rows);
Output: The result depends on an installed extension, an existing file, database records, or a randomly selected order. The code is an illustrative example and requires the environment described below.
The output demonstrates the primary operation: export PostgreSQL table rows to an array of COPY text lines.
Example 2: Understanding Another Case
This second example changes the input or option to reveal a different behavior of Pdo\\Pgsql::copyToArray().
<?php
$database = new Pdo\Pgsql("pgsql:host=localhost;dbname=demo", "app", "secret"); $lines = $database->copyToArray("stock", "|", "NULL", "code,quantity"); foreach ($lines as $line) { echo $line . "\n"; }
Output: The result depends on an installed extension, an existing file, database records, or a randomly selected order. The code is an illustrative example and requires the environment described below.
Compared with the first example, this one illustrates the same operation with a different input shape or option. Rows are raw PostgreSQL COPY text records, not decoded associative arrays. Native Pdo\\Pgsql requires PHP 8.4+ and a PostgreSQL connection.
Practical Example: A Real Application Scenario
Here is a practical use of Pdo\\Pgsql::copyToArray() with realistic sample information. Adapt the values to match your application.
<?php
$database = new Pdo\Pgsql("pgsql:host=localhost;dbname=demo", "app", "secret"); $lines = $database->copyToArray("reports", "\t", "\\N", "id,status"); file_put_contents(__DIR__ . "/reports-copy.txt", implode("\n", $lines) . "\n"); echo "Exported " . count($lines) . " rows";
Output: The result depends on an installed extension, an existing file, database records, or a randomly selected order. The code is an illustrative example and requires the environment described below.
This is a useful starting point, but production code should check errors and validate values before performing the operation. Rows are raw PostgreSQL COPY text records, not decoded associative arrays. Native Pdo\\Pgsql requires PHP 8.4+ and a PostgreSQL connection.
Important Behavior and Edge Cases
Rows are raw PostgreSQL COPY text records, not decoded associative arrays. Native Pdo\\Pgsql requires PHP 8.4+ and a PostgreSQL connection.
- Input: Use the expected PHP types and validate user-provided values.
- Result: Check the return value separately from any modifications to the input.
- Environment: For extension, database, or filesystem examples, verify availability and handle failures before accessing results.
Comparison With Related Functions
| Function or Approach | When to Use It |
|---|---|
Pdo\\Pgsql::copyToArray() | Export PostgreSQL table rows to an array of COPY text lines. |
| Related functions | copyFromArray() imports COPY-formatted lines; PDO::query() and fetchAll() return query results. |
Common Beginner Mistakes
| Mistake | Correct Approach |
|---|---|
| Assuming Pdo\\Pgsql::copyToArray() behaves like every similar function | Rows are raw PostgreSQL COPY text records, not decoded associative arrays. Native Pdo\\Pgsql requires PHP 8.4+ and a PostgreSQL connection. |
| Choosing a related operation without checking differences | copyFromArray() imports COPY-formatted lines; PDO::query() and fetchAll() return query results. |
| Ignoring prerequisites or return values | Verify extensions and data sources, and handle unexpected results explicitly. |
Key Takeaways
Pdo\\Pgsql::copyToArray()lets you export PostgreSQL table rows to an array of COPY text lines.- Rows are raw PostgreSQL COPY text records, not decoded associative arrays. Native Pdo\\Pgsql requires PHP 8.4+ and a PostgreSQL connection.
- copyFromArray() imports COPY-formatted lines; PDO::query() and fetchAll() return query results.
- Check input, return values, and environmental requirements when adapting the examples.
Pdo\\Pgsql::copyToArray() provides a focused PHP operation for export PostgreSQL table rows to an array of COPY text lines. Start with the simple examples, then adapt the practical example with the correct checks for your project.