src/includes/classes/Core/Utils/Sql.php
public function quote($value): string
    {
        if ($this->pdo_exists && $this->c::currentPdo()) {
            return $this->c::pdoQuote($value);
        }
        switch (gettype($value)) {
            case 'int':
            case 'integer':
                return (string) $value;

            case 'float':
            case 'double':
                return (string) $value;

            case 'str':
            case 'string':
                if ($this->c::isWordPress()) {
                    return "'".esc_sql($value)."'";
                }
            // Else fall through to exception.
            // no break
            default: // Unexpected data type.
                throw $this->c::issue('No SQL escape handler.');
        }
    }
public function quote($value): string
    {
        if ($this->pdo_exists && $this->c::currentPdo()) {
            return $this->c::pdoQuote($value);
        }
        switch (gettype($value)) {
            case 'int':
            case 'integer':
                return (string) $value;

            case 'float':
            case 'double':
                return (string) $value;

            case 'str':
            case 'string':
                if ($this->c::isWordPress()) {
                    return "'".esc_sql($value)."'";
                }
            // Else fall through to exception.
            // no break
            default: // Unexpected data type.
                throw $this->c::issue('No SQL escape handler.');
        }
    }
Quotes/escapes SQL value.

@since 160422 SQL utils.

@param int|float|string $value Value.

@return string Quoted/escaped value (as a string).