Can Go\'s SQL Package Handle Dynamic Queries and Table Structures?

Is Go's SQL Package Restricted to Statically Defined Queries?

Original Query:

The Go SQL documentation implies that retrieving data from a database requires static knowledge of column count and data types. This raises concerns about ad hoc queries and handling dynamic table structures.

Answer:

While it's true that Rows.Scan() requires fixed parameters, the sql.Rows type provides the Columns() method to dynamically obtain column names. Additionally, the Scan() method supports the following options:

• Using *[]byte to retrieve raw column values as a byte slice.
• Using *interface{} to obtain column values without type conversion.

Solution:

By combining these capabilities, you can create flexible code that supports ad hoc queries and dynamic table structures:

<code class="go">columnNames, err := rows.Columns()
if err != nil {
    // Handle error
}

columns := make([]interface{}, len(columnNames))
columnPointers := make([]interface{}, len(columnNames))
for i := range columnNames {
    columnPointers[i] = &columns[i]
}

if err := rows.Scan(columnPointers...); err != nil {
    // Handle error
}

// columns slice now contains decoded column values for the current row</code>

If you have additional table information, you can optimize the logic as needed.

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