return $results;
}
- /**
- * Given one xmldb_table and one xmldb_field, return the SQL statements needded to add the field to the table
- * PostgreSQL is pretty standard but with one severe restriction under 7.4 that forces us to overload
- * this function: Default clause is not allowed when adding fields.
- *
- * This function can be safely removed once min req. for PG will be 8.0
- */
- public function getAddFieldSQL($xmldb_table, $xmldb_field, $skip_type_clause = NULL, $skip_default_clause = NULL, $skip_notnull_clause = NULL) {
-
- $skip_type_clause = is_null($skip_type_clause) ? $this->alter_column_skip_type : $skip_type_clause;
- $skip_default_clause = is_null($skip_default_clause) ? $this->alter_column_skip_default : $skip_default_clause;
- $skip_notnull_clause = is_null($skip_notnull_clause) ? $this->alter_column_skip_notnull : $skip_notnull_clause;
-
- $results = array();
-
- $tablename = $this->getTableName($xmldb_table);
- $fieldname = $this->getEncQuoted($xmldb_field->getName());
-
- $defaultvalue = $xmldb_field->getDefault();
-
- $results = parent::getAddFieldSQL($xmldb_table, $xmldb_field, $skip_type_clause, $skip_default_clause, $skip_notnull_clause);
-
- /// Add default (only if not skip_default)
- if (!$skip_default_clause) {
- $default_clause = $this->getDefaultClause($xmldb_field);
- if ($default_clause) {
- $sql = 'ALTER TABLE ' . $tablename . ' ALTER COLUMN ' . $fieldname . ' SET' . $default_clause; /// Add default clause
- $results[] = $sql;
- }
-
- /// Update default value (if exists) to all the records
- if ($defaultvalue !== null) {
- if (!is_numeric($defaultvalue)) {
- $defaultvalue = "'".$this->addslashes($defaultvalue)."'";
- }
- $sql = 'UPDATE ' . $tablename . ' SET ' . $fieldname . '=' . $defaultvalue;
- $results[] = $sql;
- }
- }
-
- /// Add not null (only if no skip_notnull)
- if (!$skip_notnull_clause) {
- if ($xmldb_field->getNotnull()) {
- $results[] = 'ALTER TABLE ' . $tablename . ' ALTER COLUMN ' . $fieldname . ' SET NOT NULL'; /// Add not null
- }
- }
-
- return $results;
- }
-
/**
* Given one xmldb_table and one xmldb_field, return the SQL statements needded to alter the field in the table
* PostgreSQL has some severe limits:
$tablename = $this->getTableName($xmldb_table);
$fieldname = $this->getEncQuoted($xmldb_field->getName());
- /// TODO: Some combinations like
- /// TODO: integer->integer
- /// TODO: integer->text
- /// TODO: number->text
- /// TODO: text->text
- /// TODO: do not require the use of temp columns, because PG 8.0 supports them automatically
- /// TODO: with a simple "alter table zzz alter column yyy type new specs"
- /// TODO: Must be implemented that way. Eloy 09/2007
-
- /// If the type or the precision or the decimals have changed, then we need to:
- /// - create one temp column with the new specs
- /// - fill the new column with the values from the old one (casting if needed)
- /// - drop the old column
- /// - rename the temp column to the original name
- if ($typechanged || $precisionchanged || $decimalchanged) {
- $tempcolname = $xmldb_field->getName() . '_alter_column_tmp';
- $xmldb_field->setName($tempcolname);
- /// Create the temporal column
- /// Prevent temp field to have both NULL/NOT NULL and DEFAULT constraints
- $results = array_merge($results, $this->getAddFieldSQL($xmldb_table, $xmldb_field, NULL, true, true));
- /// Detect some basic casting options
- if ((substr($oldmetatype, 0, 1) == 'C' && $xmldb_field->getType() == XMLDB_TYPE_NUMBER) ||
- (substr($oldmetatype, 0, 1) == 'C' && $xmldb_field->getType() == XMLDB_TYPE_FLOAT)) {
- $copyorigin = 'CAST(CAST('.$fieldname.' AS TEXT) AS REAL)'; //From char to number or float
- } else if ((substr($oldmetatype, 0, 1) == 'C' && $xmldb_field->getType() == XMLDB_TYPE_INTEGER)) {
- $copyorigin = 'CAST(CAST('.$fieldname.' AS TEXT) AS INTEGER)'; //From char to integer
- } else {
- $copyorigin = $fieldname; //Direct copy between columns
+ /// Decide if we have changed the column specs (type/precision/decimals)
+ $specschanged = $typechanged || $precisionchanged || $decimalchanged;
+
+ /// if specs have changed, need to alter column
+ if ($specschanged) {
+ /// Always drop any exiting default before alter column (some type changes can cause casting error in default for column)
+ if ($olddefault !== null) {
+ $results[] = 'ALTER TABLE ' . $tablename . ' ALTER COLUMN ' . $fieldname . ' DROP DEFAULT'; /// Drop default clause
+ }
+ $alterstmt = 'ALTER TABLE ' . $tablename . ' ALTER COLUMN ' . $this->getEncQuoted($xmldb_field->getName()) .
+ ' TYPE' . $this->getFieldSQL($xmldb_field, null, true, true, null, false);
+ /// Some castings must be performed explicity (mainly from text|char to numeric|integer)
+ if (($oldmetatype == 'C' || $oldmetatype == 'X') &&
+ ($xmldb_field->getType() == XMLDB_TYPE_NUMBER || $xmldb_field->getType() == XMLDB_TYPE_FLOAT)) {
+ $alterstmt .= ' USING CAST('.$fieldname.' AS NUMERIC)'; // from char or text to number or float
+ } else if (($oldmetatype == 'C' || $oldmetatype == 'X') &&
+ $xmldb_field->getType() == XMLDB_TYPE_INTEGER) {
+ $alterstmt .= ' USING CAST(CAST('.$fieldname.' AS NUMERIC) AS INTEGER)'; // From char to integer
}
- /// Copy contents from original col to the temporal one
- $results[] = 'UPDATE ' . $tablename . ' SET ' . $tempcolname . ' = ' . $copyorigin;
- /// Drop the old column
- $xmldb_field->setName($fieldname); //Set back the original field name
- $results = array_merge($results, $this->getDropFieldSQL($xmldb_table, $xmldb_field));
- /// Rename the temp column to the original one
- $results[] = 'ALTER TABLE ' . $tablename . ' RENAME COLUMN ' . $tempcolname . ' TO ' . $fieldname;
- /// Mark we have performed one change based in temp fields
- $from_temp_fields = true;
+ $results[] = $alterstmt;
}
- /// If the default has changed or we have used one temp field
- if ($defaultchanged || $from_temp_fields) {
+
+ /// If the default has changed or we have performed one change in specs
+ if ($defaultchanged || $specschanged) {
$default_clause = $this->getDefaultClause($xmldb_field);
if ($default_clause) {
$sql = 'ALTER TABLE ' . $tablename . ' ALTER COLUMN ' . $fieldname . ' SET' . $default_clause; /// Add default clause
$results[] = $sql;
} else {
- if (!$from_temp_fields) { /// Only drop default if we haven't used the temp field, i.e. old column
+ if (!$specschanged) { /// Only drop default if we haven't performed one specs change
$results[] = 'ALTER TABLE ' . $tablename . ' ALTER COLUMN ' . $fieldname . ' DROP DEFAULT'; /// Drop default clause
}
}
}
- /// If the not null has changed or we have used one temp field
- if ($notnullchanged || $from_temp_fields) {
+
+ /// If the not null has changed
+ if ($notnullchanged) {
if ($xmldb_field->getNotnull()) {
$results[] = 'ALTER TABLE ' . $tablename . ' ALTER COLUMN ' . $fieldname . ' SET NOT NULL';
} else {
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