add support for REPLACE INTO rewriting

2024-02-22 19:11:41 -08:00
parent 23da9c0dd2
commit b33aa78976
3 changed files with 120 additions and 1 deletions
@@ -0,0 +1,107 @@
+<?php
+
+class ReplaceIntoSQLRewriter extends AbstractSQLRewriter
+{
+    public function rewrite(): string
+    {
+        global $wpdb;
+
+        $sql = $this->original();
+
+        $splitStatements = function (string $sql): array {
+            $statements = [];
+            $buffer = '';
+            $quote = null;
+
+            for ($i = 0, $len = strlen($sql); $i < $len; $i++) {
+                $char = $sql[$i];
+
+                if ($quote) {
+                    if ($char === $quote && $sql[$i - 1] !== '\\') {
+                        $quote = null;
+                    }
+                } elseif ($char === '"' || $char === "'") {
+                    $quote = $char;
+                } elseif ($char === ';') {
+                    $statements[] = $buffer . ';';
+                    $buffer = '';
+                    continue;
+                }
+
+                $buffer .= $char;
+            }
+
+            if (!empty($buffer)) {
+                $statements[] = $buffer;
+            }
+
+            return $statements;
+        };
+
+        $statements = $splitStatements($sql);
+
+        foreach ($statements as $statement) {
+            $statement = trim($statement);
+
+            // Skip empty statements
+            if (empty($statement)) {
+                continue;
+            }
+
+            // Replace backticks with double quotes for PostgreSQL compatibility
+            $statement = str_replace('`', '"', $statement);
+
+            // Find index positions for the SQL components
+            $insertIndex = strpos($statement, 'REPLACE INTO');
+            $columnsStartIndex = strpos($statement, "(");
+            $columnsEndIndex = strpos($statement, ")");
+            $valuesIndex = strpos($statement, 'VALUES');
+            $onDuplicateKeyIndex = strpos($statement, 'ON DUPLICATE KEY UPDATE');
+
+            // Extract SQL components
+            $tableSection = trim(substr($statement, $insertIndex, $columnsStartIndex - $insertIndex));
+            $valuesSection = trim(substr($statement, $valuesIndex, strlen($statement) - $valuesIndex));
+            $columnsSection = trim(substr($statement, $columnsStartIndex, $columnsEndIndex - $columnsStartIndex + 1)); 
+
+            // Extract and clean up column names from the update section
+            $updateCols = explode(',', substr($columnsSection, 1, strlen($columnsSection) - 2));
+            $updateCols = array_map(function ($col) {
+                return  trim($col); 
+            }, $updateCols);
+
+            // Choose a primary key for ON CONFLICT
+            $primaryKey = 'option_name';
+            if (!in_array($primaryKey, $updateCols)) {
+                $primaryKey = 'meta_name';
+                if (!in_array($primaryKey, $updateCols)) {
+                    $primaryKey = $updateCols[0] ?? '';
+                }
+            }
+
+            // SWAP REPLACE INTO for INSERT INTO
+            $tableSection = str_replace("REPLACE INTO", "INSERT INTO", $tableSection);
+
+            // Construct the PostgreSQL ON CONFLICT DO UPDATE section
+            $updateSection = "";
+            foreach($updateCols as $col) {
+                if ($col !== $primaryKey) {
+                    $updateSection .= ", ";
+                    $updateSection .= "$col = EXCLUDED.$col";
+                }
+            }
+
+            // trim any preceding commas
+            $updateSection = ltrim($updateSection,", ");
+
+            // Construct the PostgreSQL query
+            $postgresSQL = sprintf('%s %s %s ON CONFLICT (%s) DO UPDATE SET %s', $tableSection, $columnsSection, $valuesSection, $primaryKey, $updateSection);
+
+            // Append to the converted statements list
+            $convertedStatements[] = $postgresSQL;
+        }
+
+        $sql = implode('; ', $convertedStatements);
+
+        return $sql;
+    }
+}